How much weight your mother gained in pregnancy could influence your weight 40 years later

By Eva Martin, MD of Elm Tree Medical, Inc.

I’ve covered numerous new studies relating to the effects of weight gain in pregnancy, but the most recent study covers the longest timespan yet: forty years. Prior research has shown that excess weight gain in pregnancy predisposes infants to obesity in childhood and adolescence. But what about in adulthood? A new study followed up with daughters forty years after their mothers were enrolled in a clinical trial in the 1960’s. Read on to learn about the surprising results.

Researchers at Columbia University in New York and their colleagues reached into the archives to conduct the present study. In the 1960s, women and their children were enrolled in studies called the “Child Health and Development Studies” and the “Collaborative Perinatal Project.” In 2005 to 2008, researchers contacted the daughters to participate in a new study, the “Early Determinants of Mammographic Density Study.” 1,035 daughters in their forties enrolled in the study, and researchers collected data on their weight. The researchers also had data from the 1960s on how much weight their mothers gained during pregnancy.

The researchers compared the weight gain in pregnancy to the 2009 Institute of Medicine guidelines. Each pregnancy was categorized as either “equal to,” “greater than,” or “less than” the guidelines’ recommended weight gain.  The researchers then compared the odds of adult daughters being overweight or obese, based on their mothers’ weight gain in pregnancy. The authors controlled for the effects of the mothers’ BMI before pregnancy and the daughters’ body size at birth and in childhood. Additional statistics even accounted for their sisters’ weight, mothers’ age, and mothers’ race.

As I hinted to in the title of this blog post, mothers who gained more than the recommended amount of weight in pregnancy had daughters who were more likely to be overweight or obese in their forties. The relative increased risk of being overweight or obese was 50%. The association between pregnancy weight gain and daughter’s weight at age 40 was even stronger for mothers who started their pregnancies with higher BMIs.

While we may be tempted to call our mothers and ask how much weight they gained in pregnancy, the results do not mean that our weights are predetermined! Many of the women in the study went on to maintain healthy weights regardless of their mothers’ weight gain in pregnancy.  The study does highlight how important measures are for enabling women to gain a healthy amount of weight in pregnancy. The study also suggests that efforts to assist pregnant women with healthy weight gain now will have positive effects for generations to come. We want to hear from you! What are the best ways to encourage healthy weight gain in pregnancy? How do you advise your middle-aged patients to achieve a healthy weight and manage their risk factors for obesity?