If your patients are pregnant, they can’t eat for two. New research suggests that women who gained more than the recommended amount of weight during pregnancy had fatter children who were much more likely to develop heart disease risk factors by age 9….
Debbie Lawlor, Ph.D., senior study author and professor of epidemiology at the University of Bristol in the United Kingdom, tells us that, “I suspect that a lot of women feel that pregnancy is a time that they should eat much more and can eat more…. More studies are needed that look at the whole picture to see if there is an optimal weight that will not increase the risk of low-birth-weight babies and not increase the risk of negative outcomes in the mother and baby at the time of birth and later in their lives.”
Lawlor and colleagues found that women who gained more than the 2009 Institute of Medicine (IOM) guidelines for weight gain during pregnancy, compared with those gaining the recommended amounts, had children with:
- greater body mass indexes (BMIs), by 1 kg/2 (2.2 pounds/2)
- larger waists, by 2cm (.8 inches)
- more body fat, by 1kg (2.2 pounds)
- higher systolic blood pressure, by 1mmHg
- higher levels of inflammation markers in the blood — 15 percent higher
- lower levels of “good” cholesterol, by 0.03mmo/l (1.16009 mg/dl)
The increased weight and risk factors were particularly seen in women who gained 1.1 pounds (500 grams) or more per week after the first trimester.
The study is the most detailed examination of the association between pre-pregnancy weight or weight gain during pregnancy with childhood weight and cardiovascular risk factors, researchers said.
The IOM’s guidelines call for women who are considered underweight, with a body mass under 18.5, to gain 28 to 40 pounds during pregnancy. Those who are normal weight, a BMI of 18.5 to 24.9, should gain 25 to 35 pounds. Overweight women with BMI of 25 to 29.9 should gain 15 to 25 pounds. Obese women with BMI more than 30 should gain 11 to 20 pounds.
The study, conducted in the United Kingdom, recruited 14,541 pregnant women in 1991 – 1992. Researchers excluded women whose pregnancies weren’t full term and those carrying multiples. About 57 percent of women and their children (6,668 mother and child pairs) attended a nine-year follow-up visit. Data on maternal weight gain, childhood body measures and blood pressure was available for 5,154 of those attending the nine-year clinic and 3,457 children had complete blood work. Though women in the study were 99 percent European whites, the results should also be relevant to women in the United States — particularly those of European descent, Lawlor said.
“Pregnancy and weight gain is complex because it reflects how the baby is growing, how much water there is around the baby, how much the mother’s circulation has expanded and how much weight/fat a mother might have put on,” Lawlor said. “It is likely to be related to health outcomes in the mother and baby during pregnancy, around the time of birth, infancy and then later in life — as our results suggest.”
Therefore, Lawlor cautions against making broad statements based on this one study. “Our results show that in trying to work out what the ideal weight gain in pregnancy should be, we need to consider later outcomes in the offspring as well as outcomes around the time of birth. But, I believe we are still a long way from being absolutely clear what the optimal weight gain in pregnancy is for the best outcomes in the short and long term for both mother and child.” She also suggests trials for obese pregnant women that will randomly assign half of those in the study to receive standard prenatal care and the rest to receive standard care plus specialized advice that helps them maintain a healthy weight. This, she said, will answer more questions than observational studies such as this one.