Obese Women Retain More Pregnancy Weight
Study: 70% Gained More Weight Than Recommended
WebMD News Archive
Oct. 21, 2009 -- Gaining no weight during pregnancy or even losing a little
weight may be healthier for obese women and their babies than gaining too much
In research made public today, the investigators from Kaiser Permanente
confirmed that obese women who gain more weight than they should during
pregnancy are more likely to keep the weight on.
Nearly three out of four women in the study gained more than 15 pounds
during pregnancy, and, on average, these women retained 40% of the extra weight
a full year after giving birth.
"Younger women and first-time mothers were the most likely to gain too much
weight," obstetrician/gynecologist and study lead author Kimberly K. Vesco, MD,
tells WebMD. "The extra weight increased the risk for complications like
hypertension, diabetes, preeclampsia, C-sections, and birth injuries."
Half of Pregnant Women Overweight
Nearly half of pregnant women in the United States today are either
overweight or obese -- up from about 25% four decades ago.
Obesity is defined as having a body mass index (BMI) of 30 or more, and for
most women that means carrying at least 30 extra pounds. A BMI of 18.5-24.9 is
considered normal weight, and 25-29.9 is considered overweight.
For example, a 5-foot, 2-inch-tall woman who weighs 135 pounds would be
considered at the upper limit of the normal range (BMI = 25), and she would be
considered obese at 165 pounds (BMI = 30).
A 5-foot, 7-inch woman would be considered normal weight up to 160 pounds
(BMI = 25) and obese at 195 (BMI = 30).
The independent health policy group Institute of Medicine now recommends
that normal-weight women gain between 25 and 35 pounds during pregnancy,
overweight women gain 15 to 25 pounds, and that obese women gain between 11
and 20 pounds.
A total of 1,656 women with BMIs of 30 or more at the start of their
pregnancies were enrolled in the newly published study. The women were followed
for up to 18 months after delivery.
Putting Pregnant Women on a Diet
Some studies suggest that
babies born to obese women who don't gain much weight during pregnancy have
fewer delivery complications and better outcomes than babies born to women who
gain more weight than is recommended.
The Kaiser researchers recently began recruitment for a study examining
whether very obese women and their babies fare even better when they gain no
weight at all.
The "Healthy Moms" study, funded by a $2.2 million grant from the federal
government, will include women who are 50 to 100 pounds above their normal
weight at the start of pregnancy, Kaiser Permanente Center for Health Research
senior investigator Victor Stevens, PhD, tells WebMD.
"These are not women with just a few pounds to lose," he says. "These are
women who are carrying so much extra weight that it is a risk to themselves and