Child's Heart Risk Grows with Mom’s Weight in Pregnancy

Children of women who gain too much weight during pregnancy tend to be overweight and develop more risk factors for heart disease, says a report in the journal Circulation.

The study is based on data from women of various pre-pregnancy weights and their children up to the age of nine years.

"I suspect that a lot of women feel that pregnancy is a time that they should eat much more and can eat more," says lead author Debbie Lawlor, a professor of epidemiology at the University of Bristol in the United Kingdom.

"More studies are needed that look at the whole picture," says Lawlor.

Learning from the Experts

The report concerns women who gain in excess of the Institute of Medicine's (IOM) guidelines for pregnancy weight.

The IOM has stated that there have been dramatic changes in the population of women having babies. American women are now a more diverse group; they are having more twin and triplet pregnancies, and they tend to be older when they become pregnant.

The 2009 IOM report notes that women today are also heavier, and a greater percentage of them are entering pregnancy overweight or obese, and many are gaining too much weight during pregnancy.

For women of normal weight, that means ideal gains of between 25 and 35 pounds, whereas for overweight women the ideal gain range is from 15 to 25 pounds.

Underweight women are recommended to gain 28 to 40 pounds and for obese women the recommendation is 11 to 20 pounds.

The pre-pregnancy weight categories are based on the body mass index (BMI) scale, which takes into consideration both height and weight.

For the current analysis, the research team began tracking 6,700 women, most of them Caucasian, and their offspring for a nine-year period, starting in 1991.

In addition to maternal weight gain during pregnancy, child body measurements and blood pressure readings were repeatedly collected over the study period.

Finding the Ideal Weight Gain

Lawlor found that relative to children of mothers who stuck close to IOM guidelines, mothers who gained too much had children with greater BMIs of just over 2 lbs. (nearly an inch larger waist size), more than 2 lbs. of additional body fat, higher blood pressure, higher markers of inflammation in the blood, and lower levels of "good" cholesterol.

Such increases were most evident among children whose mothers had gained over one pound per week following the first trimester.

"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," notes Lawlor.

"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 says.

Always consult your physician or other healthcare provider for more information.