Impact of Perinatal Weight Change on Long-Term Obesity and Obesity-Related Illnesses

Abstract

Adults are becoming increasingly overweight and obese and consequently are at greater risk of such disorders as type 2 diabetes, hypertension, and cardiovascular disease. For many young adult women, pregnancy may be an event that introduces problems in controlling body weight. This study was an attempt to determine the influence, if any, of perinatal weight change on body weight and the development of obesity-related illnesses 15 years after pregnancy. The study population included 484 women who were followed up 4, 10, and 15 years after having a child. Follow up averaged 14.7 years, and the average age at this time was 43 years. During pregnancy, body weight was documented at the first prenatal visit (averaging 10 weeks gestation), at 20 weeks, and at term. The average body mass index (BMI) increased significantly between the first prenatal visit and 15-year follow up. Women who were obese initially were most at risk. At 15 years, 30% of women were obese (BMI 30 kg/m2 or higher), 27% were overweight (BMI more than 25 kg/m2), 39% had normal body weight, and 4% were underweight. Weight gain over 15 years of follow up averaged 1.4 pounds a year and 21 pounds overall. Women who were obese at baseline gained an average of 34 pounds in 15 years, averaging 2.3 pounds annually. The average yearly gain for overweight women was 1.7 pounds, and for normal-weight women, 1.2 pounds. On multivariable analysis, baseline BMI explained only 12.6% of variability in BMI. Final BMI values were highest in women who were obese when pregnant, gained more weight than recommended, retained their pregnant weight 6 months postpartum, did not exercise aerobically, or did not breast feed their infants or did so for only a short time. At follow up, 13% of women had developed diabetes or prediabetes, and 30% had developed coronary heart disease or preheart disease. Both disorders were predicted to a significant degree by baseline BMI and weight gain over 15 years. Smoking status at last follow up also significantly predicted heart disease. At 15 years, women with diabetes or prediabetes were 46 pounds heavier, and those with heart disease or preheart disease were on average 31 pounds heavier than at baseline compared with 17.5 pounds for those not affected. These findings suggest that it would be appropriate to review recommendations limiting weight gain during pregnancy. Healthcare providers should refer overweight and obese women to weight counseling not only during pregnancy, but afterward as well. There is reason to believe that, working together, providers and patients can effectively and safely control pregnancy-related weight gain, and that this may slow the increase in the rate of obesity as well as lowering the risk of obesity-related chronic illnesses.