Saturday, September 30, 2017

PCOS and Hair Loss, Part 1: Prevalence and Diagnosis


September is PCOS Awareness Month. For several years this blog has had an ongoing series about different aspects of PCOS (Polycystic Ovarian Syndrome) and its treatments. Today let's talk about a tough subject: PCOS and hair loss (alopecia).

In our past PCOS series, we have discussed the definition and symptoms of PCOS, how it presents, its testing and diagnosis, and its possible causes. We've also discussed the increased risk for endometrial cancer among those with PCOS.

Now we are discussing common treatment protocols for PCOS, and the pros and cons of each. We've already discussed insulin-sensitizing medications like metformin, the TZDs, and inositol. Then we discussed glucose-lowering medications for those who have developed overt diabetes.

We have also discussed anti-androgenic medications and progesterone supplements for menstrual irregularity. In addition, we did a 3-part series on birth control pills for PCOS.

Now it's time to talk about one of the least-discussed symptoms of PCOS, alopecia (commonly known as hair loss). Today we'll discuss what alopecia is, how it's diagnosed, and what might cause it. In the next post, we'll discuss some of the medical treatments available for it. Finally, we'll discuss some of the cosmetic treatments that women with hair loss may utilize, based on suggestions found on hair loss forums and PCOS boards.

If you have personal experience or expertise in any of these areas, please share in the comments section. Don't let other women walk this path alone; speak up and share your ideas. You are welcome to do so anonymously if you prefer. All comments should be respectful.
Disclaimer: I am not a medical health-care professional. This information is not medical advice about a health condition or treatment. Consult your healthcare provider before making any decisions about your care.
The Undiscussed PCOS Symptom

Irregular periods, sub-fertility, and excess body and facial hair (hirsutism) are the classic symptoms of PCOS, and the ones that get discussed the most on PCOS publications and boards. Acne, weight gain, insulin resistance, and blood sugar issues are other symptoms that get discussed regularly.

However, one of the least-discussed symptoms of PCOS is hair loss (androgenetic alopecia). Even acanthosis nigricans and skin tags get more discussion time on PCOS boards than hair loss.

Sadly, alopecia (and how to deal with it) is not discussed very openly, even among women with PCOS. Sometimes it's simply because the majority of women with PCOS do not experience hair loss, but often it's because of the very strong stigma of hair loss in women. Women simply do not want to admit publicly that they are experiencing hair loss, or they may be in denial about it.

For those who do experience hair loss, it's heartbreaking. Facial hair can be shaved off, but significant hair loss on the scalp is extremely difficult to deal with in a society that judges a woman on her appearance (especially her hair, her so-called "crowning glory"). Shame and embarrassment are common feelings among women with hair loss. "Fixing it" becomes the focus.

Some types of hair loss are fixable, but not all. It's important to acknowledge that up front. Unfortunately, right now there is not a lot that can be done for the type of thinning hair that comes with PCOS except to slow it down. PCOS hair loss is typically caused by the skin being ultra sensitive to androgens. Androgen-blockers can sometimes help, but in most cases, treatment for women with PCOS hair loss only results in slowing down or covering up the hair loss, not reversing it.

However, this does not mean that women with PCOS are without choices. There are many different ways of approaching alopecia, and many ways you can still have a great life despite the PCOS and alopecia. Don't let it stop you or silence your voice.

Types of Alopecia

First, it's important to understand what alopecia is, so let's start with a primer on women's hair loss.

There are many types of alopecia. Some are treatable and some are not, so it's important to know which type you have. Here are a few of the possibilities.

Alopecia Areata


Alopecia Areata (AA) is a patchy type of hair loss, rather than the overall thinning on top of the head seen with the Androgenetic Alopecia of PCOS. It often comes on quickly and results in small circular bald patches. Both men and women can experience it. According to some sources, a person has about a 2% chance of developing AA at some point during their lifetime.

Actor Matt Lucas, wikimedia commons
Some people develop Alopecia Areata Totalis, where all of the scalp hair disappears, leaving the person totally bald on the head. Another subtype is Alopecia Areata Universalis, where all body hair disappears as well as the scalp hair, including eyebrows, eyelashes, leg hair, arm hair, pubic hair ─ everything.

Alopecia Areata is due to an autoimmune condition, and as a result can come and go in severity:
In alopecia areata, immune system cells called white blood cells attack the rapidly growing cells in the hair follicles that make the hair. The affected hair follicles become small and drastically slow down hair production. Fortunately, the stem cells that continually supply the follicle with new cells do not seem to be targeted. So the follicle always has the potential to regrow hair. 
Scientists do not know exactly why the hair follicles undergo these changes, but they suspect that a combination of genes may predispose some people to the disease. In those who are genetically predisposed, some type of trigger–perhaps a virus or something in the person’s environment–brings on the attack against the hair follicles.
The good news for people with AA is that the condition is usually temporary. They have the hope of their hair growing back at some point. For most, the hair returns, but for some, the hair never does come back. Or their hair may come and go unpredictably through their lives, and they never quite know what to expect.

Mild AA can be fairly easy to deal with, from simply styling the hair a different way or applying a little scalp concealer. However, it can be very difficult to deal with severe AA, especially Alopecia Totalis or Universalis. Dealing with the loss of eyebrows and eyelashes as well as complete baldness on top is not easy, especially for women.

On the other hand, some deal with the loss quite effectively with wigs, false eyelashes, eye liner, or tatooed-on eyebrows. There are many resources for products like these here. Some celebrities have had AA and successfully hidden it, like Christopher Reeve and Neve Campbell.

Others choose not to hide their condition, like actor Matt Lucas or athlete Charlie Villanueva. They find trying to hide it a waste of time and energy and live proudly bald.

Here are some links for further information about AA:
Telogen Effluvium

Telogen Effluvium (TE) is a temporary form of hair loss and will usually resolve. It usually occurs as the result of a shock, crisis, or drastic hormonal change in the body.

Normally, hair does not continually grow on the scalp. It goes through a growing phase ("anagen") and a resting phase ("telogen"). Normally, about 10-20% of the hair follicles on your head are in a resting phase at any one time. Telogen Effluvium occurs when something causes a higher percentage of follicles to go into telogen phase, making the hair look thinner. Usually this resolves within a few months, but sometimes it takes longer or becomes chronic.

One common cause of TE is from medication which changes hormone levels, such as starting or stopping hormonal birth control like oral contraceptives. TE can also result from hormone replacement therapy, Clomid, or steroid use. Some medications for blood pressure, diabetes, hypothyroidism, anti-depressants, or high cholesterol can also cause temporary hair loss.

Probably the most common cause of TE is post-pregnancy hormone changes. The high estrogen levels of pregnancy can cause thicker and more plentiful hair, but once the estrogen levels drop after childbirth, the extra thickness and hair is lost as most of the hair goes into a "resting" phase, making the hair appear thin. It may take a while for hair to normalize, but most women with post-partum thinning go back to their normal appearance with time.

Some chronic illnesses like Crohn's Disease, IBD (Inflammatory Bowel Disease), hypothyroidism, or liver disease can cause Telogen Effluvium too. A severe shock to the system from things like car accidents, crash diets, severe stress, or serious illnesses can cause it. TE is also common after major surgery in women but may take a while to appear.

Dietary deficiencies are classic causes of TE as well. Common ones include deficiencies in iron, ferritin, biotin, protein, zinc, and certain B vitamins (especially B12), as well as too much vitamin A. Sometimes vegans are prone to hair thinning because over time they may develop a B12 deficiency. Many people who have had gastric bypass or other malabsorptive bariatric surgeries have hair fall out eventually as nutritional deficiencies accumulate over time. Eating disorders can also bring on TE.

Anagen Effluvium

Anagen Effluvium (AE) is a rapid and sudden hair loss from exposure to toxins or treatments for cancer. Chemotherapy is a common source of temporary hair loss for those with cancer because it usually targets all rapidly dividing cells. This means it targets cancer, but hair and mouth cells are also rapidly dividing cells and so are often collateral damage. Radiation treatments to the brain also often cause hair loss.

Although hair usually grows back after chemotherapy and/or radiation, it may grow back differently (changed color, straight instead of curly, change in texture). In some cases, it grows back only partially and never gets back to the fullness it used to have. Sometimes this patchiness can be quite pronounced.

Other Types of Alopecia

There are other, more rare types of alopecia as well, including Scarring Alopecia and Traction Alopecia. These result from trauma to the scalp, usually from tight hairstyles like braids, cornrows, tight ponytails, or hair extensions.

Bald spots can also result from trichotillomania, a compulsive pulling of a person's own hair. Infections can cause similiar hair loss, including fungal infections (like ringworm) and folliculitis. Diseases like lupus, congenital adrenal hyperplasia, or syphilis can also result in hair loss. And of course, age causes a gradual thinning of the hair in many people as hormones shift. About half of women experience some degree of hair loss after menopause.

Androgenetic Alopecia 

FPHL involves more diffuse thinning
Androgenetic Alopecia (also called Androgenic Alopecia, or AGA) is the term for typical female-pattern hair loss (FPHL). It is hair loss caused by genetic predisposition and excess "male" hormones or an extra sensitivity to these hormones (androgens). For this reason, sometimes it is called male-pattern hair loss in women but it does not affect women in quite the same way as it does men.

Typical male vs. female hair pattern loss differences
Women's hair loss is usually characterized by more diffuse thinning all over the top of the head behind the hairline, rather than one particular balding area as in men. Because women's hair loss usually involves gradual thinning, it is less obvious at first than hair loss in  men. However, the thinning gradually spreads so that eventually most of the top of the head experiences thinning, the scalp shows through, and the hair loss becomes more obvious. Although less common, some women also experience diffuse thinning on the sides of the head, along the front or temple-area hairline, and further down the back of the head as well.

Dihydrotestosterone (DHT), a derivative of the male hormone testosterone, is the main culprit behind hair loss in both men and women, as one website explains:
Testosterone converts to DHT with the aid of the enzyme Type II 5-alpha reductase, which is held in a hair follicle's oil glands. Scientists now believe that it's not the amount of circulating testosterone that's the problem but the level of DHT binding to receptors in scalp follicles. DHT shrinks hair follicles, making it impossible for healthy hair to survive. 
The hormonal process of testosterone converting to DHT, which then harms hair follicles, happens in both men and women. Under normal conditions, women have a minute fraction of the level of testosterone that men have, but even a lower level can cause DHT- triggered hair loss in women. And certainly when those levels rise, DHT is even more of a problem. Those levels can rise and still be within what doctors consider "normal" on a blood test, even though they are high enough to cause a problem. The levels may not rise at all and still be a problem if you have the kind of body chemistry that is overly sensitive to even its regular levels of chemicals, including hormones. 
Since hormones operate in the healthiest manner when they are in a delicate balance, the androgens, as male hormones are called, do not need to be raised to trigger a problem. Their counterpart female hormones, when lowered, give an edge to these androgens, such as DHT. Such an imbalance can also cause problems, including hair loss.
Many women with PCOS experience Androgenic Alopecia, although it is a far less common symptom than hirsutism or acne. Put another way, though hair loss rates are higher in women with PCOS than in the general population, most women with PCOS do not experience hair loss.

Why some women with PCOS experience alopecia and others do not is not clear. It probably has to do with each person's unique genetic make-up, hormone levels, and sensitivity to androgen receptors.

Summary

The bottom line is that there can be many causes of hair loss. Just because you have PCOS does not mean you could not possibly develop Alopecia Areata or have hair loss due to an underactive thyroid or a nutrient deficiency. You need to have your case reviewed by a dermatologist so you can get to the bottom of the cause of your hair loss.

Many types of hair loss are treatable and reversible, but some are not. Unfortunately, Androgenetic Alopecia, the type most common with PCOS, does not usually seem to be reversible, but there may be things you can do to slow it down. And of course, there are many practical things you can do to disguise it, if you wish to do so. Or you can simply learn to deal with the hair loss and not let it affect your happiness.

How Common is Hair Loss in PCOS?

One difficult question to answer is the incidence of alopecia in women with PCOS.

There is plenty of research documenting how much of the overall population experiences hair loss at some point in their lives, but most of this research does not differentiate between causes of the hair loss, just that it occurs at some point.

It is very difficult to separate out figures of alopecia in the general female population vs. those that are attributable to PCOS alone. First, let's start by discussing alopecia in the female population by age.

Hair Loss by Age

Most research focuses on the prevalence of hair loss differentiated by age. For example, it is estimated that about one-fourth of men begin balding by age 30, but that this increases to about two-thirds by age 60.

In women, the numbers are more uncertain. One study found that about one-third of all Caucasian women experience female-pattern hair loss (FPHL) at some point; however, a lot of this hair loss occurs after menopause. How much occurs before menopause is less clear.

One study found that about 10% of pre-menopausal women experience significant hair loss, and this number increases to about 50-75% of women over age 65. Another study found hair loss rates of about 12% of women in their 20s, which increased to 57% in women over age 80:
Twelve percent of women first develop clinically detectable FPHL by age 29 years, 25% by age 49 years, 41% by 69 years, and over 50% have some element of FPHL by 79 years. Only 43% of women aged 80 years and above show no evidence of FPHL.
How many of these women might have PCOS? It's not clear. One study of Finnish women found that about one-third experienced noticeable hair loss by age 63, and that this hair loss was often tied to strong insulin resistance. The more severe the degree of hair loss, the more severe the insulin resistance the woman likely had. Thus, it's likely that many of these women had PCOS, but the study did not look into that connection directly.

Alopecia Incidence in Women with PCOS

We do know that alopecia and PCOS are tightly tied together. One study showed that two-thirds of women experiencing hair loss had PCOS.

But this doesn't tell us the opposite; how many women with PCOS experience hair loss as one of their symptoms?

Not a lot of research exists on this question. Most studies do not quantify how many women with PCOS also have alopecia, just that it's a relatively uncommon symptom. However, recently some data has emerged, although the sample sizes in the studies are fairly small so the results vary considerably.

One British study (Sivayoganathan, 2011) found that 16% of women presenting with PCOS-like symptoms had hair loss, whereas 56% had hirsutism.

Another slightly larger study (Quinn 2014) found that 22% of women who met strict criteria for PCOS were experiencing alopecia.

Another study (Ozdemir 2010) found that 34.8% of women with PCOS had alopecia, whereas 73.9% of them had hirsutism. Similarly, Christodoulopoulou 2016 found that 36% of women with PCOS experienced alopecia.

So while most women with PCOS do not experience alopecia, between 16-36% do. In other words, between 1 in 6 and 1 in 3 women with PCOS experience hair loss. Yet even among this group, hair loss is largely ignored or talked about only minimally because of the shame and embarassment.

Interestingly, while hirsutism seems to be fairly closely correlated with androgen levels, alopecia does not. It may be less about how much androgens you produce and more about how sensitive your hair follicles are to androgens. This raises the question of whether anti-androgen medications are really an effective treatment for alopecia. (More on that in another post.)

Diagnosing Alopecia

The Ludwig Scale of Female Pattern Hair Loss (1977)
Again, if you have hair loss, it's important for you to see a dermatologist because there are so many possible causes of alopecia in women and some types are temporary or treatable. A dermatologist can help you determine which type you may have and what can be done about it.

The progression of female-pattern hair loss is usually judged on either the 3-point Ludwig Scale (above), the gradated 3-point Savin Scale (see the bottom of this section), or the 5-point Sinclair Scale (see just below). While there are other scales available, the Ludwig or Sinclair scale seems to be the most commonly used.

Sinclair Scale for hair loss
To diagnose alopecia, a dermatologist will usually do a pull test, a density test, and sometimes a scalp biopsy. Patients should provide a summary of any medications they are currently taking or have taken in the recent past. Doctors should take a detailed medical history of other conditions, including family history of hair loss and autoimmune conditions. A manual examination of the thyroid may also be indicated.

Research strongly suggests that tests for nutritional and endocrine issues also be run, including:
  • DHEAs
  • Testosterone
  • Androstenedione
  • Prolactin
  • Follicular stimulating hormone
  • Leutinizing hormone
  • Serum iron
  • Serum ferritin
  • Total iron binding capacity (TIBC)
  • Thyroid stimulating hormone (T3, T4, TSH)
  • VDRL (a screening test for syphilis)
  • Complete blood count 
  • Zinc, Vitamin D
In men, male pattern hair loss usually begins at the crown, then spreads to the temples, and progresses from gradual thinning to total bald spots. The hairline in front often recedes. In the more severe cases, men may be left only with a narrow horseshoe of hair along the back and sides of the head.

Savin Scale of hair loss
In women, the pattern is different. The hair loss begins on the top of the head, and also just behind the front hair line. The first sign is often a widening of the part in the hair, and then the hair on top of the head gradually begins to thin. It can reach down into the temple areas or on the back of the head, just below or around the crown. It is more gradual than men's hair loss, and is usually more diffuse (spread out).

Rarely do women with androgenetic alopecia lose all their hair, have a completely receding front hair line, or have complete bald spots. Instead, the hair becomes progressively thinner and more diffuse, and the scalp shows through more and more, especially in direct light. Eventually, this hair loss can become severe and become near-baldness, especially as women pass menopause.

Women's AGA alopecia tends to become noticeable later than in men, but because they are more conscious of their hair and because the social ramifications of hair loss are more severe, they tend to come in for diagnosis and treatment earlier in the process.

While hair loss is emotionally difficult for both genders, it is especially traumatic for women. Hair loss in men is common and baldness is relatively accepted; in women, it is highly stigmatized, so it is nearly always hidden away and is rarely discussed.

Summary

There are many forms of alopecia and many possible causes for it.

This is why it's important to see a dermatologist in the early stages of alopecia, so you can hopefully find some answers sooner than later. Unfortunately, many doctors are dismissive of these concerns or just put you on strong medications right away instead of trying to determine the root cause of the issue. Women on the PCOS forums stress the importance of seeing more than one doctor if necessary to get answers.

Once a cause is determined, then a course of treatment can be prescribed. Sometimes this is helpful, often it is not, but it may be worth trying just to see. More on these treatment options in the next posts.

Information is power. Make your decisions from an informed place and be aware that there is a lot of quackery and fraud in the hair loss field. People make all kinds of recommendations and claims about treatments, but very little data exists proving whether these treatments actually help.

Be very wary about claims of what can help, even from PCOS resources. Research as much as you can to learn about the benefits and risks of everything you consider trying. Be sure to visit the hair loss forums online so you can gain wisdom and support from those who have already traveled this path before you.

Above all, remember that your looks don't define you. Women with PCOS have many challenges to their self-esteem via hirsutism, acne, weight, and/or alopecia. Dealing with these challenges is frustrating and demoralizing at times, but ultimately these challenges do not define you. Only you can do that.

Remember that who you are inside is the most important thing, and that your confidence and a strong sense of self can overcome society's prejudices. 

Next post: Medications and Treatments for Alopecia


References

J Family Reprod Health. 2016 Dec;10(4):184-190.Clinical and Biochemical Characteristics in PCOS Women With Menstrual Abnormalities. Christodoulopoulou V, Trakakis E, Pergialiotis V, Peppa M, Chrelias C, Kassanos D, Papantoniou N. PMID: 28546817
...MATERIALS AND METHODS: We conducted a prospective observational study of patients 17-35 years of age with PCOS that attended the department of Gynecological Endocrinology of our hospital. RESULTS: A total of 309 women with PCOS participated in the study. In total, 72.2% suffered from menstrual cycle disorders...36% of the sample had androgenetic alopecia and 56.4% had acne....
Fertil Steril. 2014 Apr;101(4):1129-34. doi: 10.1016/j.fertnstert.2014.01.003. Epub 2014 Feb 15. Prevalence of androgenic alopecia in patients with polycystic ovary syndrome and characterization of associated clinical and biochemical features. Quinn M, Shinkai K, Pasch L, Kuzmich L, Cedars M, Huddleston H. PMID: 24534277
OBJECTIVE: To describe the prevalence of androgenic alopecia (AGA) in patients with polycystic ovary syndrome (PCOS) and to characterize associated clinical and biochemical features... SETTING: Multidisciplinary PCOS clinic at a tertiary academic center. PATIENT(S): A total of 254 women with PCOS according to the Rotterdam criteria were systematically examined from 2007 to 2012 by a reproductive endocrinologist, a dermatologist, and a psychologist... RESULT(S): Fifty-six of 254 patients with PCOS (22.0%) had AGA. Subjects with PCOS and AGA were more likely to have acne or hirsutism than those without AGA (96.3% vs. 70.6%)... There were no differences between subjects with and without AGA in biochemical hyperandrogenism or metabolic parameters. CONCLUSION(S): AGA is prevalent in 22% of subjects meeting diagnostic criteria for PCOS. AGA is associated with other manifestations of clinical hyperandrogenism, but not with greater risk of biochemical hyperandrogenemia or metabolic dysfunction than with PCOS alone.
Hum Fertil (Camb). 2011 Dec;14(4):261-5. doi: 10.3109/14647273.2011.632058. Full investigation of patients with polycystic ovary syndrome (PCOS) presenting to four different clinical specialties reveals significant differences and undiagnosed morbidity. Sivayoganathan D, Maruthini D, Glanville JM, Balen AH. PMID: 22088131
OBJECTIVE: This study aimed to compare the spectrum of polycystic ovary syndrome (PCOS) symptoms in patients from four different specialist clinics. DESIGN: A prospective cross-sectional observational study. SETTING: The study was conducted at the infertility, gynaecology, endocrine and dermatology clinics at Leeds General Infirmary, U.K. PATIENTS: Seventy women presenting with features of PCOS: 20 from infertility, 17 from gynaecology, 17 from dermatology and 16 from endocrine clinics.  INTERVENTIONS: Participants were assessed for symptoms and signs of PCOS and underwent a full endocrine and metabolic profile and a pelvic ultrasound scan. RESULTS: All subjects had experienced menstrual problems, 81% were overweight, 86% had polycystic ovaries on ultrasound, 56% had hirsutism, 53% had acne, 23% had acanthosis nigricans, 16% had alopecia and 38% had previously undiagnosed impaired glucose tolerance (IGT) or diabetes....
Acta Obstet Gynecol Scand. 2010;89(2):199-204. doi: 10.3109/00016340903353284. Specific dermatologic features of the polycystic ovary syndrome and its association with biochemical markers of the metabolic syndrome and hyperandrogenism. Ozdemir S, Ozdemir M, Görkemli H, Kiyici A, Bodur S. PMID: 19900078
...DESIGN: Prospective descriptive analysis. SETTING: University-based tertiary care. SAMPLE: One-hundred and fifteen untreated consecutive women diagnosed as having PCOS... RESULTS: The prevalence of acne, hirsutism, seborrhea, androgenetic alopecia and acanthosis nigricans was 53%, 73.9%, 34.8%, 34.8% and 5.2%, respectively. Acne was not associated with the hormonal, metabolic and anthropometric variables. Hirsutism had positive associations with total testosterone, fasting glucose and total cholesterol, and a negative association with age. Seborrhea was found to be related with free testosterone, fasting glucose and insulin. A negative association was determined among androgenic alopecia and free testosterone, low-density lipoprotein and insulin.  CONCLUSIONS: Acne and androgenic alopecia are not good markers for the hyperandrogenism in PCOS. Hirsutism appears to be strongly related with hyperandrogenism and metabolic abnormalities in PCOS women.

Friday, September 15, 2017

PCOS and Endometrial Cancer Risk: The Dilemma of Weight Loss and Weight Cycling


September is Polycystic Ovarian Syndrome (PCOS) Awareness Month. As part of our ongoing series on PCOS, today we are going to talk about endometrial cancer.

PCOS is a hormonal disorder usually characterized by very strong insulin resistance. This insulin resistance causes many problems in the body, including irregular menstrual cycles, strong susceptibility towards weight gain, unwanted hair growth on the face and body (hirsutism), hair loss on the head (alopecia), cystic acne, body tags, a strong tendency towards diabetes, infertility, and many other symptoms.

Among other risks, PCOS is associated with a high risk for endometrial cancer (cancer in the lining of the uterus). Because PCOS tends to cause an irregular menstrual cycle, a woman's uterine lining may not get sloughed off each month. Some women with PCOS have extra long cycles (35 or more days), while others go months or even years without a menstrual cycle. This causes the lining of the uterus (the endometrium) to build up excessively; in time, atypical cells may develop. This is called endometrial hyperplasia, or overgrowth of the uterine lining. This hyperplasia can eventually turn into endometrial cancer.

This is why it is so important that women with PCOS get treatment. They need to have regular periods so that this overgrowth does not occur. There are many options for this, including progesterone treatmentsbirth control pills; insulin sensitizers like metformin, TZDs, or inositols; and androgen blockers.

However, most doctors' first recommendation is weight loss.

The Weight Loss Dilemma

The majority of women with PCOS have an "overweight" or "obese" BMI. Because of the very significant insulin resistance with PCOS, these women have a strong tendency towards weight gain over time.

Women of size with PCOS face a difficult dilemma in how they approach their weight. Care providers push them to lose weight, often telling them weight loss can "cure" PCOS or get rid of most of their symptoms. Weight loss is considered by many to be the first line of therapy for PCOS.

It's true that some short-term research does seem to suggest benefits from weight loss for women with PCOS, especially in shocking the system into ovulation. But this research is almost always based on fairly short follow-ups because most weight comes back within a few years after a significant weight loss. The very loss that leads to short-term benefits may backfire later into weight gain and worsened insulin resistance.

The critical question is whether women are better off in the long term trying to lose weight, or whether the high potential for weight cycling overcomes the possible benefit of weight loss. In particular, we need to know how weight loss and weight cycling affects the chances of getting endometrial cancer.

Here are two studies that demonstrate this weight loss dilemma. One study (Luo 2017) looked at intentional weight loss in "obese" women and how that affected their risk for endometrial cancer. (The study did not look specifically at women with PCOS but weight and PCOS are so tightly tied together that weight is a pretty fair proxy for presumed PCOS when discussing endometrial cancer.)

In the study, those women who intentionally lost weight lowered their chances for endometrial cancer. The effect was particularly strong in obese women who intentionally lost weight. So if  you can lose weight and keep it off, it looks like there might be some benefit.

However, remember that the majority of women who lose weight gain it back, and often end up at a higher weight than they started. In the Luo study, women who gained weight were at increased risk for endometrial cancer. So you take a calculated risk; if you lose weight and keep it off, you might significantly reduce your risk for endometrial cancer. However, if you regain that weight and end up heavier than you started, you probably have increased your risk for endometrial cancer.

Weight fluctuations up and down the scale may also have its own independent effect. The second study (Welti 2017) found that weight cycling 4-6 times was associated with an increase in risk for endometrial cancer. Many women of size cycle far more times than that; how increased is their risk?

Summary

High BMI women with PCOS face a difficult dilemma when deciding what to do to lessen their risk for endometrial cancer.

Intentional weight loss ─ if they can keep it off ─ might lower their risk for endometrial cancer. On the other hand, if the weight loss attempt leads to weight cycling and/or overall weight gain ─ as it does for so many ─ then that weight loss attempt probably actually increases their risk. 

In other words, high BMI women with PCOS are faced with a game of Russian Roulette when it comes to weight loss and endometrial cancer.  

There are no easy answers here. Each individual woman gets to make her own choices about weight loss as a treatment for PCOS, taking into account her own personal weight history and habits.

Although most doctors don't acknowledge it, it is a perfectly reasonable choice not to pursue weight loss as a treatment for PCOS. That doesn't mean that lifestyle is irrelevant. One can choose to emphasize sensible nutrition and exercise as a treatment for PCOS without measuring the worth of those treatments by weight loss. A Health At Every Size® approach can work for PCOS.

Care providers need to recognize that their constant pressure on patients to lose weight may actually backfire and create more risk rather than less. They need to recognize the right of the patient to choose whether or not to pursue weight loss, that it is possible to emphasize healthy lifestyle without tying that to weight loss, and to acknowledge the need for multiple tools beyond weight loss to address the unique needs of their PCOS patients.



References

Cancer Epidemiol Biomarkers Prev. 2017 May;26(5):779-786. doi: 10.1158/1055-9965.EPI-16-0611. Epub 2017 Jan 9. Weight Fluctuation and Cancer Risk in Postmenopausal Women: The Women's Health Initiative. Welti LM, Beavers DP, Caan BJ, Sangi-Haghpeykar H, Vitolins MZ, Beavers KM. PMID: 28069684
BACKGROUND: Weight cycling, defined by an intentional weight loss and subsequent regain, commonly occurs in overweight and obese women and is associated with some negative health outcomes. We examined the role of various weight-change patterns during early to mid-adulthood and associated risk of highly prevalent, obesity-related cancers (breast, endometrial, and colorectal) in postmenopausal women. METHODS: A total of 80,943 postmenopausal women (age, 63.4 ± 7.4 years) in the Women's Health Initiative Observational Study were categorized by self-reported weight change (weight stable; weight gain; lost weight; weight cycled [1-3, 4-6, 7-10, >10 times]) during early to mid-adulthood (18-50 years). Three site-specific associations were investigated using Cox proportional hazard models [age, race/ethnicity, income, education, smoking, alcohol, physical activity, hormone therapy, diet, and body mass index (BMI)]. RESULTS: A total of 7,464 (breast = 5,564; endometrial = 788; and colorectal = 1,290) incident cancer cases were identified between September 1994 and August 2014. Compared with weight stability, weight gain was significantly associated with risk of breast cancer [hazard ratio (HR), 1.11; 1.03-1.20] after adjustment for BMI. Similarly, weight cycling was significantly associated with risk of endometrial cancer (HR = 1.23; 1.01-1.49). Weight cycling "4 to 6 times" was most consistently associated with cancer risk, showing a 38% increased risk for endometrial cancer [95% confidence interval (CI), 1.08-1.76] compared with weight stable women.  CONCLUSIONS: Weight gain and weight cycling were positively associated with risk of breast and endometrial cancer, respectively. IMPACT: These data suggest weight cycling and weight gain increase risk of prevalent cancers in postmenopausal women. Adopting ideal body-weight maintenance practices before and after weight loss should be encouraged to reduce risk of incident breast and endometrial cancers. 
J Clin Oncol. 2017 Apr 10;35(11):1189-1193. doi: 10.1200/JCO.2016.70.5822. Epub 2017 Feb 6. Intentional Weight Loss and Endometrial Cancer Risk. Luo J, Chlebowski RT, Hendryx M, Rohan T, Wactawski-Wende J, Thomson CA, Felix AS, Chen C, Barrington W, Coday M, Stefanick M, LeBlanc E, Margolis KL. PMID: 28165909
PURPOSE: Although obesity is an established endometrial cancer risk factor, information about the influence of weight loss on endometrial cancer risk in postmenopausal women is limited. Therefore, we evaluated associations among weight change by intentionality with endometrial cancer in the Women's Health Initiative (WHI) observational study. PATIENTS AND METHODS: Postmenopausal women (N = 36,794) ages 50 to 79 years at WHI enrollment had their body weights measured and body mass indices calculated at baseline and at year 3. Weight change during that period was categorized as follows: stable (change within ± 5%), loss (change ≥ 5%), and gain (change ≥ 5%). Weight loss intentionality was assessed via self-report at year 3; change was characterized as intentional or unintentional. During the subsequent 11.4 years (mean) of follow-up, 566 incident endometrial cancer occurrences were confirmed by medical record review. Multivariable Cox proportional hazards regression models were used to evaluate relationships (hazard ratios [HRs] and 95% CIs) between weight change and endometrial cancer incidence. RESULTS: In multivariable analyses, compared with women who had stable weight (± 5%), women with weight loss had a significantly lower endometrial cancer risk (HR, 0.71; 95% CI, 0.54 to 0.95). The association was strongest among obese women with intentional weight loss (HR, 0.44; 95% CI, 0.25 to 0.78). Weight gain (≥ 10 pounds) was associated with a higher endometrial cancer risk than was stable weight, especially among women who had never used hormones. CONCLUSION: Intentional weight loss in postmenopausal women is associated with a lower endometrial cancer risk, especially among women with obesity. These findings should motivate programs for weight loss in obese postmenopausal women.

Thursday, August 31, 2017

Lower Surgical Threshold, Less Patience in Labor for "Obese" Women


Here is yet another study (Ellekjear 2017) showing that labor is often managed differently in "obese" women, with a lower surgical threshold being the most marked finding. The authors concluded:
Caesarean deliveries are undertaken earlier in obese women compared to normal weight women following the onset of active labour, shortening the total duration of active labour.
Research generally shows women of size probably need more time in labor in general, especially in the early stages, but once their labors get going, they usually go well. However, many care providers opt to terminate labor earlier and move quickly to a cesarean. They are understandably concerned about the risks of doing an emergent cesarean on a larger body, but they are usually giving up far too soon and causing an epidemic of "failure to wait" cesareans in women of size. .

There was an infamous Vaginal Birth After Cesarean (VBAC) and obesity study in 2001 that demonstrated this quite strongly. 30 women over 300 lbs. were "allowed" to labor for a VBAC, but only 13% of those who tried for a VBAC ended up with one. As a result, this was widely publicized as a reason not to "let" high-BMI women try for a VBAC and cited by doctors as a reason to deny fat women the opportunity to VBAC.

However, what the full text of the study actually reveals is that the majority of these women were induced, which is known to increase the chances of cesarean and lower the chances of VBAC. Interestingly, the only women who got a VBAC in this study were the ones who were not induced.

Most tellingly, those who had cesareans had their labors stopped at an average of 4.5 cm of dilation. 4.5 cm barely qualifies for the old definition of active labor, and certainly doesn't fit with the new recommended definition of active labor (6 cm)! In other words, these high BMI women were not given an adequate chance to labor.

High induction rates and a lack of patience in labor are the main factors that drive the high cesarean rate in obese women. 

Studies have shown that about half of high BMI women in general are induced, typically increasing cesarean rates. However, when allowed to go into spontaneous labor, cesarean rates are more equalized among BMI groups.

One earlier study found that high BMI women tended to take longer to progress in labor, especially between 4 and 7 cm of dilation. They urged far more patience in the labors of heavier patients.

Similarly, a 2016 study found that 57% of labors in high BMI first-time mothers were stopped before 6 cm of dilation; those mothers ended with cesareans. Failure to Wait is a major problem when doctors attend women of size.

More spontaneous labor and more time during labor would probably have yielded far better VBAC rates in that 2001 VBAC study. It should be pointed out that a look at some later studies showed VBAC rates around 50-70% in obese women, which could almost certainly be increased even more since they also reflect very high induction rates and the old active labor definition. Indeed, research from England shows that the majority of even very high BMI women can have a vaginal birth with different management.

The bottom line is that multiple studies have found that the labors of high BMI women are managed differently than the labors of average-sized women. 

In particular, too many inductions are being done, the surgical threshold is very low, and more patience is needed during labor. This represents an area that is ripe for change and offers hope for lowering the far-too-high cesarean rate in obese women. 

As the authors of a Canadian study concluded about the management of high BMI women:
Because of the potential morbidities associated with Caesarean section, we must modify our management approaches to allow equal opportunity for a vaginal birth for all women.

Reference

BMC Pregnancy Childbirth. 2017 Jul 12;17(1):222. doi: 10.1186/s12884-017-1413-6. Maternal obesity and its effect on labour duration in nulliparous women: a retrospective observational cohort study. Ellekjaer KL, Bergholt T, Løkkegaard E. PMID: 28701155
...METHODS: Retrospective observational cohort study of 1885 nulliparous women with a single cephalic presentation from 37 0/7 to 42 6/7 weeks of completed gestation and spontaneous or induced labour at Nordsjællands Hospital, University of Copenhagen, Denmark, in 2011 and 2012. Total duration of labour and the first and second stages of labour were compared between early-pregnancy normal-weight (BMI <25 kg/m2), overweight (BMI 25-29.9 kg/m2), and obese (BMI ≥30 kg/m2) women. Proportional hazards and multiple logistic regression models were applied. RESULTS: Early pregnancy BMI classified 1246 (66.1%) women as normal weight, 350 (18.6%) as overweight and 203 (10.8%) as obese. No difference in the duration of total or first stage of active labour was found for overweight (adjusted HR = 1.01, 95% CI 0.88-1.16) or obese (adjusted HR = 1.07, 95% CI 0.90-1.28) compared to normal weight women. Median active labour duration was 5.83 h for normal weight, 6.08 h for overweight and 5.90 h for obese women. The risk of caesarean delivery increased significantly for overweight and obese compared to normal weight women (odds ratios (OR) 1.62; 95%CI 1.18-2.22 and 1.76; 95%CI 1.20-2.58, respectively). Caesarean deliveries were performed earlier in labour in obese than normal-weight women (HR = 1.80, 95%CI 1.28-2.54). CONCLUSION: BMI had no significant effect on total duration of active labour. Risk of caesarean delivery increased with increasing BMI. Caesarean deliveries are undertaken earlier in obese women compared to normal weight women following the onset of active labour, shortening the total duration of active labour.

Sunday, August 20, 2017

Researchers' Goof: Transverse CS Incisions ARE Better in High BMI Women!


EXTRA, EXTRA! 

Researchers messed up the conclusion of earlier cesarean incision study! 

Transverse (side-to-side) incisions really are better after all for high BMI women! 

Vindication! 

Background

For many years OBs were taught that a vertical incision was needed for very "obese" women because the area under a belly flap ("panniculus", sometimes referred to as a "pannus") was hot and moist and therefore prone to infection ─ in other words, an area just waiting to cause wound complications. One OB wrote in 2006:
In general, there is a lot to be said for an incision not buried under the pannus of fat, so that fresh air can help keep the wound dry.
As a result, many OBs were taught that when they did cesareans on high BMI women, vertical (up-down) incisions should be used instead of low transverse (side-to-side, either Pfannenstiel or Joel-Cohen) incisions in order to lower the risk for infection, separations, and other wound complications.

WRONG! Example of incorrect teaching illustration
about vertical incisions and obesity
They meant well, but they were operating from flawed assumptions and outdated teaching. In other words, they hadn't actually studied whether or not vertical was better in high-BMI women, they just assumed it was, based on their biases about fat bodies. As the authors of Alanis 2010 state:
Our results...contradict classic teaching by veteran surgeons and obstetrical texts. It has been written that transverse abdominal incisions made under the pannicular fold exist in “a warm, moist, anaerobic environment associated with impaired bacteriostasis . . .[that] promotes the proliferation of numerous microorganisms, producing a veritable bacteriologic cesspool.” However, we are unable to locate any evidence to support this popular conclusion....
A "veritable bacteriologic cesspool"? What a terrible and disrespectful way for those obstetric texts to describe it. While deep skin folds can sometimes predispose to skin yeast and infections, it doesn't always and surgical incisions should not be based on conditions assumed to exist. Rather, care providers should be aware of the possibility and make decisions based on actual evidence of problems rather than an assumption of pathology.

Vertical Incisions Do Not Improve Outcomes


As noted, cesarean incision choice for very heavy women was usually based on traditional teachings and biased assumptions. When someone actually took the time to research these hypotheses, however, it was found that vertical incisions were no better, and in some studies were actually far more risky.

Let's do a quick review of the medical literature on this topic.

Vertical is More Risky

The Alanis 2010 study discussed above studied women with a BMI over 50. They found better outcomes with transverse incisions:
Vertical abdominal incisions were associated with increased operative time, blood loss, and vertical hysterotomy...Our results also support the use of Pfannenstiel incisions in obese patients with a large panniculus.
D'heureux-Jones 2001 also found that vertical incisions were associated with greater blood loss and poorer outcomes. They recommended a Pfannenstiel incision too.

In some studies the findings were more dramatic. In Wall 2003, vertical incisions presented 12x the risk for wound complications compared to transverse incisions. TWELVE TIMES the risk. That's a tremendous difference.

Thornburg 2012 found that the majority of wound complications (WC) were found in the vertical incision group (45.7% rate in vertical incisions, vs. 11.6% in transverse incisions). That's a very significant difference. They concluded:
In morbidly obese women both infectious and separation type WC are more common in vertical than low transverse incisions; therefore transverse should be preferred.
Vertical is No Improvement

Critics would point out that a number of studies did not find a statistically significant difference between vertical vs. low transverse incisions (Sutton 2016, Vermillion 2000McLean 2012, Houston and Raynor 2000Brocato 2013, and Bell 2011). Many researchers cite these studies to argue that there is no difference between incisions and the choice should be completely left to the surgeon's preference.

However, if they read the full text of these studies, the data usually showed a very clear trend towards more complications with vertical incisions. For example, 5 of the 6 above-cited studies found nearly double or more the rate of problems in the vertical incision group, yet the difference did not rise to statistical significance:
  • Bell 2011 found wound complications in 14.6% of the vertical incision group vs. 7.6% in the low transverse group
  • Vermillion 2000 found a 23% wound infection rate in the vertical group vs. a 6% rate in the low transverse group
  • McLean 2012 found a 20% rate of wound separation in the vertical group vs. a 10% rate in the low transverse group
  • Sutton 2016 found a 26.3% rate of wound complications in the vertical group vs. 14.8% in the low transverse group 
  • Brocato 2013 found 2.7x the risk for wound complications in the vertical group
The problem here is that the number of patients in the vertical incision groups in these studies was extremely small and that is what is confusing the outcome. Bell 2011 had only 41 patients with vertical incisions; Brocato 2013 had only 45; Sutton 2016 had only 57; McLean 2012 had only 25; and Houston and Raynor 2000 had only 15 patients in their vertical comparison groups. Basically, the studies showing no significant difference had too few vertical incisions to be rigorously compared. 

The fact that the differences didn't rise to statistical significance doesn't mean that vertical incisions were just as safe; it just means that these studies were simply underpowered to show statistical significance between the groups. 

Summary

Larger studies do need to be done, but the majority of the evidence we have so far suggests that vertical incisions perform no better and often perform worse in obese women. Low transverse incisions are usually associated with better outcomes. 

Bottom line, vertical incisions are associated with increased rates of wound complications, blood loss, and infections in obese women, even very obese women, as we have written about extensively before. In addition, vertical incisions are far more scarring and challenging to a woman's self-esteem and should ideally be avoided on that basis alone. It's also worth noting that although the best incision for each woman's unique anatomy and situation must be judged on an individual basis, low transverse incisions have been used successfully even in women of 400-500 pounds without poor outcomes.

Vertical Skin = Vertical Uterine Incisions

Image from swcare.net

Another problem is that several of these studies (Bell 2011, Alanis 2010, Sutton 2016) have also shown that when vertical skin incisions are done, they result in a higher rate of vertical uterine incisions (hysterotomies). Bell 2011 found that nearly 2/3 of all vertical skin incisions in obese women resulted in a vertical uterine incision as well.

A vertical uterine incision results in a riskier surgery, with more blood loss, a more difficult recovery, and a higher rate of uterine rupture in future pregnancies. In most OB practices, it limits a woman's future delivery choices to automatic repeat cesareans, which may have tremendous long-term health implications for the mother due to increased placental abnormalities and intraoperative injuries. The Alanis 2010 authors noted:
Vertical abdominal incisions were associated with vertical hysterotomy in our study, usually a result of inadequate access to the lower uterine segment. When the incision extends into the contractile portion of the uterus, a vertical hysterotomy has a profound impact on future pregnancy. Therefore, it is important to incorporate practices, like transverse abdominal incisions, that facilitate low uterine incisions.
Doing a vertical incision routinely and without pressing need in high BMI women subjects them to more risk and potentially limits their future reproductive choices. As a result, one reviewer concluded that in obese women:
Low transverse skin incisions and transverse uterine incisions are definitely superior and must be the first option.
In recent years, more and more OBs began to use low transverse incisions in women of size. In fact, today the vast majority of high BMI women ─ even very high BMI women ─ who have cesareans have low transverse incisions. This is encouraging progress.

Still, many OBs cling to their teaching and use a vertical incision at a higher rate for obese women, especially "morbidly obese" and "super obese" women.

2016 survey of OBs revealed that while 84% preferred a transverse incision for obese women, 16% still preferred other incisions (usually vertical).

McLean 2012 found that 11% of high-BMI women were still being subjected to the riskier vertical incisions; Marrs 2014 (a very large, multi-region, multi-center study; see below) found that vertical incisions were used in a whopping 19% of high BMI women.

Between these documents, that's a vertical incision in about 1 out of every 5-10 cesareans done in obese women. So while progress has been made, vertical incisions are still distressingly common, and they are still putting the well-being of women of size at risk.

But What About That 2014 Study?



Some doctors have pointed to the Marrs 2014 study to justify continuing with vertical incisions. This was the one study that seemed to disprove the idea that transverse was better. (See the first abstract below, full text can be found here.)

This was a secondary analysis of the MFMU registry, which examined data from cesareans in 19 different regional hospitals. This analysis looked at incision complications after cesarean in women with a BMI of 40 or more. Since it was the largest study of its kind in obese women (597 vertical incisions, 2603 transverse incisions), its conclusions were assumed to be far more powerful and definitive.

In the study, wound complications were found in 1.7% of women with transverse incisions vs. 4.2% of women with vertical incisions. In other words, more than double the rate of problems were found with vertical incisions. Simple conclusion to be drawn, right? Not quite.

In its univariate (one variable) analysis, transverse was shown to be the safer incision. But in its multivariate (multiple variable) analysis, the opposite was found ─ vertical seemed better. This conclusion was trumpeted far and wide because now there was research ammo to keep justifying the use of vertical incisions in high-BMI women.

However, a re-analysis of the data shows that their conclusion was wrong and transverse was better after all. Turns out they used the wrong figures in their multivariate analysis and so got the wrong conclusion. Instead of vertical being the better incision, it was actually transverse that had the best outcomes. The authors issued a retraction in July of 2017 and stated:
The original publication reported that univariate analysis showed that a vertical skin incision in obese women undergoing Cesarean delivery was associated with a higher odds ratio for wound complications than a transverse skin incision. Multivariable analyses showed a reversal of the association (i.e. the odds of wound complications were lower in women with a vertical skin incision). However, there was an error in the way the variable was entered in the logistic analysis. Re-analysis with the correct coding of the variable indicates that a transverse skin incision is associated with decreased odds of wound complication compared to a vertical skin incision.
Well, bravo that they finally published a retraction to the previous study and a corrected abstract...3 years after the fact. (I have published the abstracts to both below for comparison.)

At least they actually printed a retraction and admitted their error. Usually these are just glossed over. But I'm irritated because the damage has been done. How many OBs have gotten the wrong impression and won't see the retraction? How many young doctors have been erroneously taught that vertical incisions were superior for high BMI women?

When you search online, the original manuscript with its erroneous conclusions still pops up without any corrections, and is still being cited by some doctors as evidence that a vertical incision is just as good or better.

How many high-BMI women have had the more dangerous vertical incision in the meantime and how many will continue being subjected to it because of the error in that original study? How many medical schools and textbooks will continue teaching that vertical incisions are better?

Grrrrrrrr. Mistakes happen, but this is a mistake with long-lasting implications for larger women. I can't believe they were sloppy enough to make this mistake in the first place and then not discover it for three years. I also question whether they are doing enough to reach out to correct the mistaken teaching and care practices that are in place because of this egregious error. If it's not addressed aggressively, incorrect teachings and practices will remain in place, and that could have a lot of negative health implications for women of size.

Conclusion

Low transverse cesarean scar in a high BMI woman;
these are usually minimally noticeable after a few years


A vertical skin incision on a high BMI woman has far more noticeable
scarring and potential impact on her self-esteem

The cesarean rate in obese women is unconscionably high. Some cesareans are needed of course, but many cesareans in high BMI women are planned pre-labor cesareans, and many labor cesareans could probably be avoided with more patience, fewer inductions, a more lenient surgical threshold, and different management in labor.

But the fact of the matter is that around half or more of all obese mothers in many areas of the U.S. are being subjected to cesareans. The rate of wound complications increases with BMI in a dose-respondent manner, so the question of how to lower complications in obese women is extremely pressing.

Proper choice of cesarean incision is one key way to reduce complications in obese women. Thankfully, most OBs recognize that a low transverse is the best incision in high BMI women, and use it most of the time.

However, some OBs continue to insist that vertical is better, especially as BMI increases. One 2014 study found only a 2% rate of vertical incisions in women with BMIs between 30 and 40, but this increased to more than 15% in women with a BMI over 50. The fact that the Marrs MFMU study found that vertical incisions were used in 19% (nearly 1 in 5 cesareans of obese women) in women with a BMI over 40 is quite alarming. These high rates are risking the health and well-being of women of size.

Furthermore, OBs have even been known to use a vertical incision to discourage their "morbidly obese" patients from having more children. This is appalling example of weight stigma. Here is one woman's story:
When she came in to discuss my surgery, the OB sat down and asked me if I wanted my tubes tied while she was in there. I was shocked and told her no, that this was my first child, and I didn't want to make decisions like that at the moment. And she countered with a speech that boiled down to 'You are too fat to have any more children, you shouldn't even be having this one, and if I had anything to do with it, you wouldn't be.'...[Afterwards] the hateful OB informed me that the kind of incision that they made in my uterus will make it incredibly dangerous for me to attempt another pregnancy...a subsequent pregnancy could cause the uterus to rupture and I would die horribly from a hemorrhage.
Granted, there are sometimes circumstances which compel the use of a vertical incision. An extremely large belly makes it harder to locate anatomical landmarks; sometimes the panniculus is so large it is impossible to place an incision beneath it; sometimes there is an active skin infection present in the folds; sometimes other factors like fetal or placental position make a different incision safer. In those situations, there are other incision options, including a vertical or a higher transverse (Joel-Cohen) incision. However, this mother had none of these considerations. The incision seems to have been chosen purely to punish the mother and to strongly discourage further children despite her refusal of sterilization.

Whatever the reasons, there is no justification for such a high rate of vertical incisions still being used in heavy women. Medical schools and educational materials need to stop teaching that a vertical incision is the incision of choice for high BMI women.

Research CLEARLY shows that a vertical incision performs no better than a transverse one in obese women and in most research, is actually associated with worse outcomes. NO study now shows a better outcome with vertical incisions. 

The bottom line is that incision choice for each woman of size must be evaluated on its individual circumstances, but a low transverse incision should be the default choice in nearly all high BMI women. As one OB said in a conference presentation to colleagues:
The bottom line is that vertical incisions should not be used in obese patients...Vertical incisions are being used less and less in these patients, but just don't do it.

References

Original Article

Am J Obstet Gynecol. 2014 Apr;210(4):319. doi: 10.1016/j.ajog.2014.01.018. Epub 2014 Feb 20. The relationship between primary cesarean delivery skin incision type and wound complications in women with morbid obesity. Marrs CC, Moussa HN, Sibai BM, Blackwell SC. Full text here.
OBJECTIVE: We sought to evaluate the relationship between skin incision, transverse or vertical, and the development of wound complications in women with morbid obesity requiring primary cesarean delivery (CD). STUDY DESIGN: Morbidly obese women (body mass index ≥40 kg/m(2)) undergoing primary CD at ≥24 weeks' gestation were studied in a secondary analysis of a multicenter registry. Clinical characteristics and outcomes were compared between women who had transverse vs vertical skin incision. The primary outcome was composite wound complication (infection, seroma, hematoma, evisceration, fascial dehiscence) and composite adverse maternal outcome (transfusion, hysterectomy, organ injury, coagulopathy, thromboembolic event, pulmonary edema, death). Multivariable logistic regression analyses were performed to adjust for confounding factors. RESULTS: In all, 3200 women were studied: 2603 (81%) had a transverse incision and 597 (19%) had a vertical incision. Vertical skin incision was associated with lower risk for wound complications (adjusted odds ratio, 0.32; 95% confidence interval, 0.17-0.62; P < .001) but not with composite adverse maternal outcome (adjusted odds ratio, 0.72; 95% confidence interval, 0.41-1.25; P = .24). CONCLUSION: In morbidly obese women undergoing a primary CD, vertical skin incision was associated with a lower wound complication rate. Due to the selection bias associated with utilization of skin incision type and the observational nature of this study, a randomized controlled trial is necessary to answer this clinical question.
Retraction and Revised Conclusion

Am J Obstet Gynecol. 2017 Jul;217(1):85. doi: 10.1016/j.ajog.2017.06.002. Removal notice to The relationship between primary cesarean delivery skin incision type and wound complications in women with morbid obesity: Am J Obstet Gynecol 2014;210:319.e1-4. Marrs CC, Moussa HN, Sibai BM, Blackwell SC. PMID: 28648694
This article has been removed: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been removed at the request of the Editors-in-Chief and Authors. The original publication reported that univariate analysis showed that a vertical skin incision in obese women undergoing Cesarean delivery was associated with a higher odds ratio for wound complications than a transverse skin incision. Multivariable analyses showed a reversal of the association (i.e. the odds of wound complications were lower in women with a vertical skin incision). However, there was an error in the way the variable was entered in the logistic analysis. Re-analysis with the correct coding of the variable indicates that a transverse skin incision is associated with decreased odds of wound complication compared to a vertical skin incision.

Studies Which Show Poorer Outcome with Vertical Incisions in Obese Women
Small Studies Which Show No Statistically Significant Difference
My Previous Writings on Skin Incisions in High BMI Cesareans