Eating for two? Most pregnant women today have been warned by their doctors not to follow that outdated and potentially harmful adage.
In fact, there are significant risks to both mother and baby when women gain too much weight during pregnancy or are overweight or obese when they become pregnant. The obesity epidemic that has engulfed the U.S. has resulted in larger-than-ever numbers of women facing potential health risks during pregnancy.
“When it comes to pregnancy, being overweight or obese is not just a matter of personal appearance, it is a matter of potentially endangering the lives of both a mother and her fetus,” said Dr. Carol Major, director of UCI Health Maternal-Fetal Medicine.
Major and other maternal-fetal medicine specialists, also known as high-risk obstetricians, have become valuable assets for pregnant women with weight-related health problems.
Risks of obesity during pregnancy
For overweight and obese women, the risks are many.
- They have a two to three times higher risk of developing gestational diabetes, a form of diabetes that develops during pregnancy.
- There is a three-fold increase in risk of preeclampsia, compared to normal-weight pregnant women. This is characterized by high blood pressure and other symptoms in the later stages of pregnancy and, if untreated, can lead to dangerous conditions for both mother and baby.
- They have a two to threefold risk of having an exceptionally large baby (macrosomia), which can lead to an increased risk of cesarean section and an increased risk of birth trauma during delivery.
- There is an increased risk of miscarriage, stillbirth and certain types of birth defects.
A pre-pregnancy body mass index (BMI) of 30 or greater is defined as obese. According to a 2015 study published in the American Journal of Obstetrics & Gynecology, 48 percent of U.S. women were overweight at the start of pregnancy and about 48 percent of women gained too much weight during pregnancy.
Link to diabetes later in life
Studies have shown that maternal health can have a significant impact on the in-utero environment and thus on fetal development and the health of the child later in life. Babies who are very large at birth are more likely to develop obesity and type 2 diabetes later in life.
"Basically, the nutritional environment results in in-utero fetal programming during pregnancy," Major says. "These babies are being programmed to have a higher risk of obesity."
High-risk obstetricians try to prevent all of these complications, starting with advising their patients about proper weight gain. For example, a woman with a BMI of 30 or greater is advised to limit pregnancy weight gain to 15 pounds. Overweight women are advised to gain only 15 to 25 pounds (compared to 25 to 30 pounds for normal-weight women).
Special care during pregnancy
It is important for overweight or obese women to receive special care during their pregnancy, Major said.
"We see these patients on a frequent basis so that we can identify complications earlier and treat them to prevent more serious problems.
"Fortunately, pregnancy is a time when most women are highly motivated to take care of themselves and will usually do whatever they can for their babies."
Nutrition and exercise
The patients receive counseling about nutrition and exercise to minimize excessive weight gain and improve the patient’s health-related habits.
"We can really minimize the risk of developing certain pregnancy problems," Major says. "We put these patients on a healthy diet and work with them to minimize the weight gain. By doing this, we can decrease the likelihood of patients’ developing gestational diabetes and blood pressure elevations."
Exercise is also prescribed for pregnant women, even if it's as little as lifting small hand weights while sitting on the couch watching television.
Women are also counseled on the need to maintain healthy diet and exercise habits, even after they give birth. An estimated 50 percent to 70 percent of women who develop gestational diabetes will go on to develop type 2 diabetes later in life, Major says.
High-risk obstetricians even see women prior to pregnancy for preconception counseling, Major says. Some overweight or obese women have difficulty becoming pregnant because extra weight can interfere with ovulation.
"We encourage them to lose weight before they get pregnant," she says. "Even losing 5 percent to 7 percent of their current weight, such as 10 to 20 pounds, will make a significant difference that can improve outcomes."
In addition to pre-pregnancy diet and exercise, it is recommended that some women consider bariatric surgery prior to becoming pregnant. Patients who have undergone bariatric surgery are advised to wait 12 to 24 months after surgery before becoming pregnant.
Best outcomes after complicated pregnancies
UCI Health high-risk obstetricians offer comprehensive services and have some of the best outcomes in the country for management of complicated pregnancies. The multidisciplinary team of experts includes obstetricians, perinatologists (experts in high-risk pregnancy), geneticists, endocrinologists (who specialize in diabetes), cardiologists and many other specialists.
"We're here to get great outcomes for moms and babies," she says. "The link between obesity and diabetes is not just a pregnancy issue; it's a life issue. You're motivated during pregnancy, but you have to be around for your child after birth. We encourage women to continue with these healthy changes."