Hypothyroidism and Pregnancy

Over at the blog, the-f-word, the author has had a series of recent posts discussing hypothyroidism. This is a topic of special importance when discussing pregnancy and postpartum issues so I thought I'd highlight it here too.

[There's no need to repeat all her information, so we'll just mention a few points particularly pertinent to pregnancy and postpartum, and then tell you to GO READ IT. ]

Many fat folk have undiscovered or undertreated hypothyroidism. Doctors often do not take hypothyroidism concerns seriously in fat people, thinking they are trying to excuse their supposed eating problems. So it can be difficult to find a care provider who is willing to take these concerns seriously or test them in any meaningful way.

Furthermore, exactly what TSH levels should be used to diagnose hypothyroidism is controversial. Newer diagnostic cutoffs favored by some medical groups tend to diagnose and treat more people; the older cutoffs miss a lot of borderline or "subclinical" cases. Yet these folks often experience typical hyothyroidism symptoms like:

• obesity/unexplained weight gain/difficulty losing weight
• tiredness/fatigue
• very dry or cracked skin
• menstrual problems/irregularity
• dry/brittle hair and nail changes
• muscle or joint aches and pains
• feeling cold a lot/intolerance to temperature variations
• depression issues
• "brain fog"
• constipation
• fertility issues

If you have a combination of these symptoms you might want to consider thyroid testing. However, if you do have thyroid testing, BE SURE TO GET YOUR EXACT RESULTS AND THE DIAGNOSTIC CUTOFFS USED TO DEFINE "NORMAL." Compare your exact results to the levels considered "normal" and see where your levels fall.

Too often, people are told their results are "normal" when in fact, closer examination may show that their results are borderline (and should be watched and retested later) or are actually abnormal when using the newer, lower cutoffs.

[I really can't stress this enough. Do NOT just accept a "normal" or "abnormal" on lab tests; actually get the numerical results, the range the lab used to determine "normal" and compare them. Then request a copy of your lab results and keep a record of them so you can track them over time. Remember, lots of people who may have been diagnosed as "normal" in the past might now be considered to have "abnormal" results now under revised guidelines.]

Thyroid Tests and Pregnancy Concerns

If you are considering pregnancy at any time in the near future, you might want to have your thyroid levels checked as a precaution beforehand, even if you don't suspect a problem.

Some doctors these days recommend that ALL women have their thyroid levels checked before or during pregnancy, but it's not certain whether this broad a testing distribution is really justified by research. More study is needed before such widespread testing is implemented.

However, for women of size (and especially those with PCOS), it probably is sensible to have the thyroid levels checked before pregnancy. Although not all research agrees, some research suggests that obese people tend to have higher rates of both overt and subclinical (or "mild") hypothyroidism. Other research suggests that women with PCOS also have more subclinical hypothyroidism. Therefore, it probably makes sense for women in these two groups to have their thyroid levels checked carefully, preferably well before conception.

For some women, it also makes sense to check thyroid levels during pregnancy as well. If you have had thyroid issues in the past (or suspect them), are being treated currently for hypothyroidism, or if you have a strong family history of hypothyroidism, you should have your levels monitored regularly during pregnancy.

Even if your hypothyroidism was well-controlled beforehand, it may not stay that way during pregnancy, and can change fairly quickly. Therefore, periodic testing during pregnancy is a must for those with hypothyroidism.

Your levels should be measured about every trimester, on average. However, some women need to increase their thyroid medication dosage even early in the first trimester. If your thyroid levels historically have bounced around a lot, you may be particularly susceptible to early problems and should be closely monitored. If you haven't seen your midwife or OB yet, your family doctor/GP can help you get the tests you need until you have a care provider for your pregnancy.

Does Hypothyroidism Make a Pregnancy High-Risk?

Some women with hypothyroidism have been told that their hypothyroidism makes them "high risk" and so they are not good candidates for a birth center or home birth, or that they should only see an OB or even a perinatologist during pregnancy.

However, it's only UNTREATED or INADEQUATELY TREATED hypothyroidism that is really a risk. As long as thyroid levels are tested periodically and treated adequately, women with hypothyroidism don't need to be treated as "high-risk." Most women with adequately-treated hypothyroidism have normal, healthy pregnancies and babies. (I did, four times, and so have many other women with hypothyroidism that I know.)

Unless thyroid levels are particularly difficult to keep under control, women with hypothyroidism can see any type of provider they wish...nurse-midwife, homebirth midwife, family doctor, or OB.

Nurse-midwives and doctors all can order thyroid tests and adjust prescriptions as needed; homebirth midwives often can order lab tests and work with consulting doctors to make prescription adjustments if needed. Any of these types of care providers can provide care for a pregnant woman with hypothyroidism.

Some women prefer to be followed by both a pregnancy care provider and an endocrinologist, as they feel their endocrinologists may pay closer attention to smaller changes in their thyroid levels. Others do not feel the need for care beyond their normal provider.

Hypothyroidism does not preclude you from birthing at home or at a birth center, nor does it necessitate a high-risk provider. Choose whatever provider you feel most comfortable with. However it's a good idea to ask your care provider about his/her plan for monitoring your thyroid levels during pregnancy; some care providers are more knowledgeable about thyroid concerns than others. Be sure they also have a plan for checking your levels postpartum.

Postpartum Thyroid Issues

After the baby is born, many women experience thyroid difficulties. Even if you've never had thyroid issues in your life, were fine during pregnancy, or were totally fine in all previous pregnancies, you may still develop postpartum thyroiditis. It is important to watch ALL women carefully for thryoid symptoms after birth.

Postpartum thyroiditis classically involves a period of hyPERthyroidism (thyroid is overactive) followed by hyPOthyroidism (thyroid is underactive). However, be aware that some women skip straight to the hypothyroidism part and never experience any real signs of hyperthyroidism first.

About 5-10% of all women develop postpartum thyroiditis, but the incidence is higher in women with a history of thyroid or autoimmune issues. Doctors often miss postpartum thyroiditis since they usually only see you briefly several weeks after the baby is born. And with a new baby, many moms tend to dismiss symptoms or don't take time to have them investigated. So postpartum thyroiditis tends to be underdiagnosed and the incidence may be higher than generally acknowledged.

Women experiencing difficulty with breastmilk production should have their thyroid levels tested (as well as testing for anemia etc.), because this can affect milk production. There are many other possible causes of low milk production, of course, but this is one that is often missed. And because thyroid levels can fluctuate widely after childbirth, repeated testing may be needed. Although most women with a history of thyroid issues can breastfeed without problems, they should be particularly watchful for possible thyroid issues.

Women who gain a lot of weight in the months after giving birth (despite normal intake and despite breastfeeding) may also be experiencing postpartum thyroid issues and should be checked.

Women who experienced severe bleeding during and after birth should also be aware of a potential for thyroid problems. Sometimes severe hemorrhage can damage the pituitary gland, which in turn can lead to hypothyroidism. This is called Sheehan's Syndrome. As one website notes:

Rarely, hypothyroidism after childbirth is caused by Sheehan's syndrome, also called postpartum hypopituitarism. This condition may occur in women who have severe blood loss during childbirth resulting in damage to the anterior pituitary gland.

Finally, women who experience thyroid issues during and after pregnancy should also be warned to watch for possible recurrence of thyroid issues during perimenopause and menopause. Advanced age is another period of time when women are particularly vulnerable to hypothyroidism too. Thus, periodic thyroid tests should become part of women's life-long care.

Thyroid Medicine and Supplements

Hypothyroid medications are generally considered safe during pregnancy and breastfeeding. Remember, these medications are simply putting back into your body what should already be there. Babies are at far greater danger from untreated hypothyroidism than they are from typical hypothyroid medications. Just make sure to monitor your thyroid levels periodically.

I know of no "official" correlation between hypothyroidism and vitamin D levels, but it's my observation that many folks with hypothyroidism also have chronically low vitamin D levels as well. Whether there's a causal connection is debatable, but they often do seem to go hand in hand. So while you are at the doctor's having your TSH etc. checked, consider asking them to run Vitamin D levels as well.

Finally, remember that many things interfere with absorption of thyroid medicines. In particular, thyroid meds should NOT be taken at the same time as prenatal vitamins. (Many doctors don't know this; mine didn't.) Iron and calcium in particular interfere with absorption of thyroid medications, and prenatals are full of iron and calcium. Take your thyroid meds and your prenatals at least 2-3 hours apart instead.

Take your thyroid meds as consistently as possible. Thyroid meds are most effective taken in the morning, on an empty stomach, with plenty of water. Avoid eating for about an hour afterwards if possible. Do not take with any other meds or vitamins, and if possible, take them about the same time each day.

Conclusion

Although most women will not have problems with their thyroid during their pregnancies or postpartum, the frequency with which it occurs (even in women with no prior thyroid issues) merits close attention from birth attendants.

However, because not all birth attendants are fully aware of hypothyroidism issues in pregnancy, women need to be proactive about informing and advocating about this issue for themselves, particularly women of size.