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Myths and Truths of Obesity and Pregnancy

Vitamins, Weight Gain, Preterm Birth and More

Wednesday, December 21, 2011

Newborn baby

When thinking about pregnancy, many women who struggle with extra weight may receive a lot of misinformation from doctors and health systems. There is every indication that women who carry extra weigh can have a happy and health pregnancy, but there may be challenges that patients and their doctors must manage to achieve the best possible outcome for the pregnant person and their baby. 
In the journal Seminars in Perinatology, maternal fetal medicine expert Loralei L. Thornburg, M.D., reviews many of the pregnancy-related changes and obstacles women with obesity may face. The following myths and truths highlight some expected and some surprising issues to take into account before, during and after pregnancy.
“I treat patients who struggle with weight all the time, and while everything may not go exactly as they’d planned, they can have healthy pregnancies,” says Thornburg, who specializes in the care of high-risk pregnancies and conducts research on the best care for women with obesity during pregnancy. “While you can have a successful pregnancy at any size, patients need to understand the challenges that their weight might create and be a partner in their own care; they need to talk with their doctors about the best way to optimize their health and the health of their baby.”
Myth or Truth? Obesity alone is a major risk factor in pregnancy.
While women of size may need additional care or monitoring during their pregnancy, most otherwise healthy women of any size will have successful and healthy pregnancies.  
However, many women of size have underlying medical disorders than have contributed to their struggles with weight, or are pregnancy concerns on their own. Medical conditions like autoimmune disorders are often treated with long-term steroids, which can lead to diabetes and weight gain. In women with these conditions, the underlying immune condition can be much more of a concern for the pregnancy than the extra weight.
Additionally, conditions like diabetes are particularly prone to getting out of control in pregnancy. There are specific changes in hormones that make it harder to control blood sugars during pregnancy, and most women will need frequent adjustments in insulin as the pregnancy progresses. For these conditions, as well as many others, women of size may need to seek specialist care (such as care with a maternal fetal medicine physician) in addition to routine pregnancy care to help assure a good pregnancy outcome.
Myth or Truth? Many women with obesity are vitamin deficient.
Maybe, especially in those patients with prior gastric surgeries.
Up to 40 percent of patients with obesity are deficient in iron, 24 percent in folic acid and 4 percent in B12. This is especially true in patients who have had gastric surgeries for weight loss, as portions of the stomach and small intestine are typically bypassed during these surgeries, reducing absorption of key nutrients. This is a concern because certain vitamins, such as folic acid, are very important before conception, lowering the risk of cardiac problems and spinal defects in newborns. Other vitamins, such as calcium and iron, are needed throughout pregnancy to help babies grow. 
Thornburg says vitamin deficiency has to do with the quality of the diet, not the quantity. There is a concern that women with obesity, especially those living in food deserts and other places where food choices are limited, may not get enough servings of fortified cereals and fruits and vegetables, and may eat more processed foods that are high in calories but low in nutritional value.
“Just like everybody else, women considering pregnancy or currently pregnant should get a healthy mix of fruits and vegetables, lean proteins and good quality carbohydrates. Unfortunately, these are not the foods people lean toward when they overeat, and not the foods that are easily available or the most affordable,” notes Thornburg. “However, frozen vegetables have the same nutrition as fresh, and might be another way to increase vegetable and fiber intake at a reduced cost. Ideally, patients should be taking vitamins containing folic acid before and during pregnancy.”  
Myth or Truth? Women who are overweight or obese need to gain at least 25 pounds during pregnancy.
In 2009, the Institute of Medicine revised its recommendations for gestational weight gain for women with obesity from “at least 15 pounds” to “11 to 20 pounds.” According to past research, women of size with excessive weight gain during pregnancy have a very high risk of complications, including indicated preterm birth, cesarean delivery, failed labor induction, large-for-gestational-age infants and infants with low blood sugar.
If a patient starts her pregnancy overweight or obese, avoiding excessive weight gain can actually improve the likelihood of a healthy pregnancy, Thornburg points out. Talking with your doctor about appropriate weight gain for your pregnancy is key, she says.
Myth or Truth? The risk of spontaneous preterm birth is higher in women with obesity.
Women of size have a greater likelihood of indicated preterm birth – early delivery for a medical reason, such as maternal diabetes or high blood pressure. But, paradoxically, the risk of spontaneous preterm birth – when a woman goes into labor for an unknown reason – is actually 20 percent lower in women with obesity. There is no established explanation for why this is the case, but Thornburg says current thinking suggests that this is probably related to hormone changes that may decrease the risk of spontaneous preterm birth.
Myth or Truth? Respiratory diseases – including asthma and obstructive sleep apnea – increase the risk for non-pulmonary pregnancy complications, such as cesarean delivery and preeclampsia (high blood pressure).
Patients who carry extra weight have increased rates of respiratory complications, and up to 30 percent experience an exacerbation of underlying asthma during pregnancy - a risk almost one-and-a-half times higher than other patients. According to Thornburg, respiratory complications are often undertreated in all women and increase the likelihood of problems in pregnancy. She stresses the importance of getting asthma and any other respiratory conditions under control in ALL patients before getting pregnant.
Myth or Truth? Breastfeeding rates are high among women of size.
Breastfeeding rates are poor among women of size, with only 80 percent initiating and less than 50 percent continuing beyond six months, even though it is associated with less postpartum weight retention and should be encouraged as it benefits the health of mom and baby.
Thornburg acknowledges that it can be challenging for any woman to breastfeed, and women of size can struggle additionally due to stigma and body shaming. Additionally, women with obesity may have delayed lactation (it often takes longer for their milk to come in) and they can have lower production (breast size has nothing to do with the amount of milk produced).
Indicated preterm birth, a higher pregnancy complication rate and a high cesarean delivery rate can all result in prolonged separations of patient and baby, especially if the infant is admitted to the neonatal intensive care unit (NICU).  The higher rate of maternal complications and cesarean delivery – up to 50 percent in some studies – can make it harder to successfully breastfeed due to surgical and medical recovery. This, coupled with the lack of consistent understanding from lactation consultants about supports and help needed for women to successfully breastfeed when facing challenges, can decrease rates of breastfeeding.  
“Because of these challenges, mothers need to be educated, motivated and work with their doctors, nurses and lactation professionals to give breastfeeding their best shot. Even if you can only do partial breastfeeding, that is still better than no breastfeeding at all,” says Thornburg. “If you have the opportunity to meet with a lactation team ahead of delivery, this can make the difference in having a plan for how to be successful and knowing who to turn to when it is not going as expected.”  
For more information from Thornburg, read “Pregnant Women of Size: What to Expect and Not to Expect!”

Loralei L. Thornburg, M.D.
Loralei L. Thornburg, M.D.

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