As I review the research on "obesity" and pregnancy, it always strikes me what's missing from this research.
Santa, since you are Patron of the Plus-Sized, I'd like to request some improvements as my Christmas gift this year. Could you whisper in some researchers' ears and plant the following suggestions?
Do More Meaningful Research
First, I'd like to request that researchers stop going for the easy publishing hits and start making their research more meaningful. For example, most research on obesity and pregnancy now is just a litany of risks....fat women have more risk for "x" or "y" ─ but without any insight as to why they are more at risk for these things. Study after study reiterating a litany of risks is not very meaningful anymore, but it does tend to ratchet up doctors' perceptions of risk around obesity, especially when they only use odds ratios instead of actual numerical risk.
I think it's well-established that women of size are more at risk for certain things....the question is what can we do about it. That's where our focus needs to be in obesity and pregnancy research right now; not just documenting increased risk but what to do about it. And that leads us directly to the next item on my Dear Santa List.....
Research Improving Outcomes Without Weight Loss
Without fail, nearly every study pushes weight loss as the answer to Life, the Universe, and Everything. Yet they stubbornly fail to connect the dots from other research that clearly shows that long-term weight loss is extremely unlikely, and that weight loss attempts often actually lead instead to further weight gain.
If the only tool in our toolkit for improving outcome is one that is extremely unlikely to succeed, then it's time to develop some new tools in the toolkit. We must start looking beyond weight loss as the only answer to improving outcomes.
Distinguish Between Correlation and Causation
I would love to see more obesity research differentiate between correlation and causation when it comes to obesity. Just because a certain outcome is associated with obesity does not mean obesity causes it (or that weight loss cures it). In fact, a third factor common to both may actually be the cause...or some factor we don't understand yet.
I'd love to see researchers consider the possibility the obesity is a symptom of an underlying difference (in genetics, in metabolism, in hormonal issues, in ability to process insulin, etc.), rather than the automatic cause of problems. If obesity is just another symptom, then focusing on weight loss is just a band-aid approach (and would explain why weight loss is often unsuccessful). Focusing on the exact cause would lead to more improvement in outcomes long-term, which is what we really want, isn't it?
We have to move beyond our "blame the victim" mentality around obesity (i.e., obesity is a voluntary state caused mostly by bad behaviors), and start considering the possibility that obesity may often be simply another symptom of an underlying physical or metabolic difference.
Examine Interventions to See If They Improve Outcome
Many interventions to improve outcome have been proposed for women of size, especially "morbidly obese" women. RCOG, the British version of ACOG, recommends that morbidly obese women be put on a low-dose aspirin regimen prophylactically to try and lower the rate of pre-eclampsia in this group. The SOGC (Canadian version of ACOG) now recommends that morbidly obese women be put on regimens of ultra-high dose folic acid to try and lower the rate of birth defects in this group. Yet both of these recommendations were undertaken without research to show that they improve outcome, nor am I aware of any current studies looking to see if such regimens improve outcome.
Doctors often recommend care regimens in fat women in hopes that they will reduce poor outcomes, but without follow-up testing to see if these interventions improve outcome. For example, as we recently discussed, doctors were taught for years that a vertical incision would lower the wound complication rate in very obese women, but when someone finally actually did a study of this question, they found that vertical incisions actually performed more poorly.
There's nothing wrong with proposing a potential intervention to see if it improves outcome in women of size (and prophylactic aspirin or high-dose folic acid may actually be a reasonable precaution for at least some very heavy women), but researchers have to then follow up and examine whether the proposed intervention actually improves outcomes or not.
Ideas for Specific Studies I'd Love To See
Antibiotic Dosing - In size acceptance circles, we've been saying for years that weight-based dosing may be needed to improve outcomes in people of size after surgery (depends on the type of antibiotic and its mechanism of action; some need weight-based dosing and some do not). But we've consistently had difficulty in getting care providers to actually do this.
A recent study showed that 2 g of cefazolin given shortly before a planned cesarean did not reach minimal inhibitory concentration to knock out gram-negative bacteria in nearly half of morbidly obese women. Since cefazolin is the antibiotic of choice in many surgical procedures (especially cesareans), it's time for a randomized controlled trial to find out what the optimal dosage for morbidly obese women actually is.
This shouldn't be that hard or that difficult a study to do; it's beyond me why it hasn't been done already. And it's vital that this be done, since chronically underdosing obese people may be adding to the increasing societal problem of antibiotic-resistant bugs, not to mention worsening outcomes among women of size.
Midwifery Model of Care - I'd love to see a study that specifically compared outcomes for obese women who experienced a low-intervention, "midwifery" model of care, vs. obese women who experienced a high-intervention, high-risk "bariatric obstetrics" model of care. Research clearly shows that cesarean rates are lower for most women who experience a midwifery model of care, but there is no study that directly compares the two models of care specifically for obese women.
Given the strong move in many places to deny women of size the right to access low-intervention midwifery care ─ or even just regular obstetric care ─ and "alternative" options like waterbirth, birth centers, and homebirth, it behooves us to examine the which model of care actually improves outcomes better in this population. What data we have and anecdotal stories suggest that the midwifery model will be advantageous for women of size who do not experience severe complications ─ but we need direct studies of the issue to confirm or deny that.
Fetal Malpositions - I'd love to see another modern study examine whether women of size have more malpositioned babies. Many very old studies mention a common perception that obese women have higher rates of malposition, and there is one modern study that confirms nearly twice the rate of posterior babies in obese women ─ but we really need more than that. From the stories women have submitted to me (and from my own experiences), it seems like more women of size have malpositions, and this may be a prime reason behind our higher rates of labor dystocia and slower labors, but it'd be really useful to be able to show that conclusively.
If we can document more malpositions in women of size, then we could raise awareness of the possibility among care providers and then use chiropractic care (to prevent malpositions) and manual rotation techniques (to lower the c-section rate associated with OP babies during labor) to improve outcomes. And perhaps we could keep care providers from just assuming that inefficient uterine contractions and/or soft tissue dystocia is always to blame, as they usually do now.
Bottom line, if we can elucidate whether or not there are increased rates of malpositions in women of size, we can incorporate the interventions that improve outcome when malpositions are encountered (chiropractic care, maternal repositioning, more patience during labor, manual rotation) and probably lower the cesarean rate in women of size.
Iatrogenic Factors in Cesarean Rates - A couple of recent studies have found that the labors of obese women were managed differently, with far more interventions, more inductions, and a lower threshold for surgical delivery. When these factors are controlled for, the higher cesarean rate in obese women was either markedly attenuated or it completely disappeared. I'd love to see more follow-up on these studies in a similar vein.
The high cesarean rate in women of size is not only about direct iatrogenic factors, but they do likely play a strong role in it. Until care providers are willing to objectively look at their own role in poorer outcomes, care will not improve markedly in this group.
Compare Those with Good Outcomes to Those with Poorer Outcomes - Researchers need to start acknowledging that many women of size have good outcomes and start studying these women. They need to compare women who had good outcomes vs. those who had poorer outcomes and see if they can gain more clues about underlying causes of problems.
For example, if obese women who experience pre-eclampsia have higher hyperinsulinemia rates than obese women who do not experience pre-eclampsia, then perhaps treating women with metformin or fixing insulin receptor/signaling issues will help lower the rates of pre-eclampsia. Or if obese women who experience a birth defect have lower pre-existing folate stores, then pre-conception blood testing and treating those with low folate stores will help prevent more birth defects in this group. Or if they find that obese women who do not develop GD have consistently higher exercise rates than those who do develop it, then increasing exercise rates is an easy intervention to promote.
The point is that at this point, everyone is so busy blaming and shaming the fat mother for complications that virtually no one is exploring why some fat women have great outcomes and some do not. Examining the differences between the two groups might help elucidate the real causes of complications in women of size, and might give some really concrete directions for improving outcome.
PCOS and Breastfeeding - There is some preliminary research that shows that PCOS can impact milk supply and lower breastfeeding rates, but we have very little data on how many women with PCOS are affected, and why some with PCOS are affected and others are not.
Research on the impact of PCOS on milk supply has been out for more than 10 years, yet little follow-up research has been done, and rarely is this confounding factor even mentioned in studies on why breastfeeding rates are lower in women of size. Nor has anyone studied possible interventions (metformin, goat's rue, progesterone supplements, etc.) to see if these could improve milk supply in affected PCOS women. Considering how important breastfeeding is to a mother and baby's long-term health, it's long past time for far more attention to be paid to this issue.
Health at Every Size® and Pregnancy Outcome - Again, if weight loss before pregnancy is the only tool in our toolkit for improving outcome, we are greatly limiting our choices. A Health At Every Size approach has been shown to improve outcomes in non-pregnant women; might it improve outcomes in pregnancy too?
We need to uncouple weight loss from exercise and promotion of healthy habits in the research. When "lifestyle interventions" are shown to improve outcome, was it really from the minimal weight loss associated with these interventions, or from the increased levels of exercise and improved habits instead? If we focus on exercise and improved habits, will we improve outcomes without risking the long-term weight gain so commonly associated with weight cycling? We need research targeted to this question, and we need it now.
Thanks for listening, Santa. I will be waiting with bated breath for studies on these topics and a general improvement in the direction of research around obesity and pregnancy.
Researchers and care providers, are you listening too? Wouldn't you like to be a Santa's Helper and help improve outcomes among women of size? A more thoughtful and targeted approach to research on obesity and pregnancy would go a long way towards achieving that goal.