Maternal Obesity from All Sides
[Editor's note: In this, our last segment of the Maternal Obesity from All Sides series, Pamela Vireday shares with us some thoughts regarding prevention, and lived experiences of women of size. To read the series from the beginning, go here. Thank you to ALL of our contributors to this important series. Haven't shared this conversation with your social media circle yet? Take a moment to Tweet it or share it on Facebook!]
Rethinking Prevention and Treatment
Maternity care providers usually consider only 3 ways to improve patient outcomes: weight loss before or between pregnancies, restricting gestational weight gain, or incorporating high-intervention care models. Let’s look at these approaches first, and then examine some alternatives as well.
Weight Loss Before/Between Pregnancies
The Holy Grail of Prevention in most researchers’ minds is weight loss before or between pregnancies. But is this wise?
Research strongly supports the idea that significant weight gain before pregnancy increases the risk for complications, leading doctors to focus on the idea of weight loss preventing them. In fact, some research does support weight loss as prevention. However, this weight loss can come at a price.
Many women of size who lose weight between pregnancies report gaining significantly more in the subsequent pregnancy; 41% compared to 18% in one study. Chronic dieters also tend to have more excessive weight gains in their pregnancies. Furthermore, a history of weight loss or frequent weight cycling is a strong predictor of subsequent large gain outside of pregnancy, and long-term weight loss maintenance is rare.
This is not to say that the weight loss option cannot be discussed with women; some may be desirous of this approach. However, women also have the right to decline it. An alternative approach may be to choose a “Health at Every Size” program ─ emphasizing healthy habits independent of weight loss status.
Prenatal Weight Gain Restriction
More and more, researchers have been focusing on restricting prenatal weight gain in high-BMI women in order to improve outcomes. However, recommendations for optimal prenatal weight gain in this group are hampered by study design issues, lack of uniform definitions of obesity and weight gain categories, and contradictory findings.
Research does suggest that high weight gains are associated with increased rates of cesareans, macrosomia and pre-eclampsia. However, causal interpretations for this are questionable. Iatrogenic factors influence the cesarean rate because of the fear of macrosomia and lack of blinding about weight gain. And higher weight gain is most likely a side-effect of pre-eclampsia, not a cause of it. Only macrosomia seems closely tied to high weight gain.
Even so, many care providers are now pushing ultra-low gain policies for their obese patients. However, this is not without risk. Research shows that there are increased rates of adverse outcomes with this approach, including small-for-gestational–age (SGA) infants, prematurity, and perhaps infant mortality.
At this time, the Institute of Medicine recommends a weight gain of 11-20 lbs. for all obese women. Emerging research suggests that optimal weight gain may differ by class of obesity, but doctors must balance the risks of SGA and prematurity against the risks of macrosomia and cesareans carefully, especially for mid-sized obese women (BMI 30-40). Placing a pregnant woman into a fat and protein-burning state for maintenance of energy levels may not be the best thing—for mother and fetus, alike.
Furthermore, studies that examine lifestyle interventions in obese pregnant women show mixed results. Some show reduced gain, while others showed little difference or even increased gain instead. Many show little difference in birth weight, complications, mode of delivery, or neonatal outcome. If reduced gain makes little difference in outcomes, why risk it?
Remember, good nutrition should always be the priority over rigid weight gain goals; altering prenatal weight gain through scorched-earth interventions may cause more harm than benefit. And researchers must be careful that focusing on weight gain goals does not encourage punitive practices or overly restrictive advice among clinicians.
Ghettoizing Women of Size
Increasingly, research calls for high-BMI women to be managed as “high-risk” patients. In practice, this means that obese women are often not considered eligible for low-intervention care models and “alternative” birth choices. Some care providers are even declining to see high-BMI patients at all.
Obese women increasingly report being “ghettoized” into “bariatric obstetrics” practices, unable to access local OBs, midwives, or community hospitals. Many report not being allowed to have a homebirth, birth center birth, waterbirth, or even a VBAC. Many are strongly pressured into a high rate of interventions with few alternatives.
Some providers assume that outcomes will be better with high-intervention protocols across the board, but this has not been proven. While sometimes interventions are needed, anecdotally many women of size find that high-tech care models result in poorer outcomes, more traumatizing births, and more interference with breastfeeding.
Research shows that outcomes are good for other women with midwifery care, even women with “moderate” risk factors. And since many obese women do have normal pregnancies and births, obese women without serious complications should still be able to choose midwifery care, community hospitals, “alternative” care, and low-tech models of care. To paraphrase Susan Hodges of Citizens For Midwifery, how much perceived ‘risk’ does it take to supercede a mother’s right to patient autonomy?
When researchers fixate on weight loss, weight gain restriction, and high-intervention care models as the only methods of preventing problems, they lose the opportunity to explore other sensible avenues of prevention.
The most basic way to improve outcome is to emphasize the importance of a pre-conception check-up to check blood pressure, blood sugar, thyroid function, and prenatal vitamin/folic acid intake. These are vital because the most serious complications in obese women usually come from those with uncontrolled pre-existing conditions. The importance of good nutrition and exercise for preventing complications should be discussed, but without lecturing and moralizing.
The importance of exercise is perhaps the most potent message for women of size to hear for minimizing complication rates. In one study, the risk for GD in obese women was cut nearly in half by regular exercise. Some studies suggest it may lower the risk for pre-eclampsia as well. Studies in non-pregnant people show that exercise can improve health greatly, independent of weight loss.
Restrictive dietary advice is controversial. Many care providers advise obese clients to limit high glycemic-index carbohydrates, but research on this approach is contradictory . A Cochrane review found some benefits but overall inconclusive results. Since many women of size are insulin-resistant, it seems sensible to encourage complex carbs combined with protein, since this significantly improves glucose and insulin response. That being said, caution should be taken in implementing a low glycemic index diet; severe carbohydrate restriction can result in a ketogenic state—putting both mother and baby at increased risk.
It has long been speculated that a higher dose of folic acid might lower the risk for birth defects in obese women, and some organizations recommend doing this. Other resources recommend measuring red blood cell count folate concentration instead and giving additional supplementation only for those with low concentrations.
Some experts have also speculated that supplementation with higher doses of vitamin D before or during pregnancy might help prevent some cases of gestational diabetes, hypertension disorders, and cesareans. However, research so far has been mixed.
Another preventive option that has been proposed by some organizations is daily low-dose aspirin after the first 12 weeks for those obese women most at risk for pre-eclampsia. Like folic acid and vitamin D, this too needs to be studied further for efficacy and safety but is an intriguing possibility. Because aspirin intake during pregnancy can result in deleterious outcomes in some mother/baby dyads, antenatal aspirin use should only be maintained under the careful guidance of the woman’s maternity care provider.
Care must be taken not to use a too-small BP cuff, which artificially inflates blood pressure readings and can result in over diagnosis of hypertensive disorders. Large arms over 34 cm need a large cuff, and some need a thigh cuff. Care must be taken with forearm readings, as these tend to overestimate blood pressure too.
Anecdotally, many women of size (like all women) find that avoiding inductions is an important part of improving their outcomes. Indeed, one study of obese women found a c-section rate of 19% with spontaneous labor (vs. 41% for induced labor), and that induction was the start of many complications in this group. Because induction rates can be as high as 50% in very obese women; avoiding induction may help lower cesarean and complication rates. Adjusting due dates for menstrual cycle length may also help reduce the number of inductions for postdates pregnancies in high-BMI women.
A tincture of patience in labor may be helpful too. Many cesareans occur because of a “failure to wait” among care providers. Since their first stage of labor tends to be slower and because many care providers opt for cesareans more quickly in obese women, it’s important to allow a truly adequate labor before opting for surgery.
Many high-BMI women report having cesareans for fetal malpositions, and some research supports this. This suggests that interventions such as manual rotation skills or prophylactic chiropractic care might help lower their rate of cesareans. Anecdotally, many women of size report that chiropractic care was very helpful in pregnancy and labor.
Re-examination of surgical care regimens may also improve outcomes in those who do have cesareans. For example, many clinicians were taught to use vertical incisions and subcutaneous drains in cesareans in very obese women, yet recent research finds these actually increase the risk of wound complications strongly. Additionally, a higher dose of antibiotics may be needed in morbidly obese women, and those who develop infections may benefit from extended treatment with more frequent dosing regimens.
However, the most powerful measure for prevention in the pregnancies of women of size is simply having a care provider that does not see them as a ticking time bomb, who understands that large bodies can work “right” too, and who truly believes in their potential to give birth vaginally as well. Remember the power of the self-fulfilling prophecy; be proactive about complications but expect normalcy.
Weight loss before pregnancy is something that can be considered on an individual basis for those who wish it, but we cannot place all our prevention eggs in one basket.
High-BMI women should probably avoid very high weight gains, but extreme interventions to restrict weight may increase the risk for some adverse outcomes as well and must be viewed with caution.
Forcing all obese women into a high-risk, high-intervention care model penalizes those without complications and may cause more harm than good. Women of size, like all women, deserve the right to patient autonomy and access to care that will improve their outcomes.
Clearly, the pregnancies of high-BMI women carry a higher risk for some complications. It is important to care about lessening this risk and promoting proactive care. However, we must not let hyperbole about this risk rush us into unwise, ineffective, and even dangerous interventions. We must start examining other options for prevention as well.
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