The U. S. Department of Health and Human Services has long touted that children with overweight or obese parents are more likely to become overweight themselves. Recent research supports that lifestyle factors are not the sole cause of this phenomenon. According to researchers from The Children’s Hospital of Philadelphia and the University of Pennsylvania School of Medicine, a woman who gains a significant amount of weight during her pregnancy is more likely to have a child who becomes overweight by age 7.

Brian Wrotniack, Ph.D., and his team of investigators reviewed data from the Collaborative Perinatal Project, a multicenter, retrospective study that consisted of 10,226 participants between 1959 and 1972. Surveys provided to women who participated in the study included questions regarding maternal pre-pregnancy weight, age and race. Moreover, maternal weight gain and a child’s growth during pregnancy, at birth and at age 7 were also recorded.

The results of the study are astounding as the odds of a child being overweight at age 7 increased by 3 percent for every 2.2 pounds of pregnancy weight gained by the mother. According to the Institute of Medicine (IOM), the quantity of weight gain during pregnancy is contingent on the mother’s starting weight prior to pregnancy. The IOM recommends that women at a healthy pre-pregnancy weight gain 25-35 pounds, while women who are considered overweight should gain 15-25 pounds.

Researchers concluded that children born to women who gained more than the recommended levels were 48 percent more likely to be overweight. The association between pregnancy weight gain and the child’s excess weight in later years remained significant even after adjusting for factors such as gender, gestational age, infant birth weight, race, age, and maternal BMI percentage. Another study conducted by Emily Oken, MD, MPH, at Harvard Medical School also found that gestational weight gain is directly associated with BMI and risk of obesity in adolescence. This research supports findings that obesity rates influenced by gestational weight gain are not only limited to childhood but also advances well into the teenage years.

Pregnancy weight gains have increased over the years as obesity has escalated into a public health crisis. Dr. Wrotniack and his team maintain that one in two women (46%) gain more weight than recommended during pregnancy. Substantial weight gain during pregnancy is now considered one of the earliest determinants of obesity in children. Counseling women to adopt healthy eating habits and increase physical activity before and during pregnancy may be effective ways to prevent future obesity risk in children and adolescents.