Excess weight is one of the less graceful side effects of pregnancy. For some women, the weight is easily shed after giving birth, and within a year they are back in their pre-pregnancy jeans. For others, it’s not as easy. Based on a new study, those who fail to lose their baby weight within a year of giving birth are faced with more serious complications than just a fuller figure. Failure to lose excess baby weight increases the risk for diabetes and heart disease.

The experiment, led by Dr. Ravi Retnakaran, followed 305 obstetrical patients at Mount Sinai Hospital in Canada. It was the first study to measure women’s weight patterns a year after they had given birth and check them for metabolic and cardiovascular risk factors. Results showed that nearly three-quarters of the women were able to successfully lose some weight a year after giving birth. These women were also able to maintain healthy levels of cholesterol and blood pressure.

For the quarter of women who were unable to lose any weight by the year after they gave birth, researchers saw a clear increase in risk factors for diabetes and cardiovascular disease. The test results prove a clear correlation between failure to lose weight between three and 12 months after giving birth and difficulties with blood pressure, cholesterol, and insulin. “This finding helps us to advise women about the importance of losing their excess pregnancy weight in the first year after delivery,“ Retnakaran explained in a recent press release.

Although it was already suspected that failure to lose pregnancy weight had the potential to cause health complications, the study yielded some ground-breaking results regarding a window of opportunity in regard to weight loss. Research showed that increased health factors observed 12 months after giving birth had not been present at three months after giving birth.

“That means that the nine-month window leading up to one year after birth is a critical time for women to ensure that they are losing at least some of their pregnancy weight," Retnakaran concluded. Although the results are promising, more research needs to be conducted in order to help women maintain a healthy weight after they give birth. The study hopes to widen its scope and test the weight and metabolic risk factors of women up to two or three years after they have given birth.

Source: Kew S, Ye C, Hanley AJ, et al. Cardiometabolic Implications of Postpartum Weight Changes in the First Year After Delivery. Diabetes Care. 2014