Pregnant women gaining more weight than that recommended are at a greater risk of death from heart disease or diabetes later in life, according to a study published in The Lancet journal.
The increased mortality risk was found for all weight groups studied, including those defined as underweight, normal or overweight prior to their pregnancies, the researchers said, having analysed more than 45,000 US women’s data 50 years, including their body mass index (BMI) and weight fluctuations during pregnancy.
No heightened risk was, however, found in women who were obese prior to pregnancy, the team of researchers, led by those from the Perelman School of Medicine at the University of Pennsylvania, said.
”We showed that gaining weight during pregnancy within the current guidelines may protect against possible negative impacts much later in life, and this builds upon evidence of the short-term benefits for both maternal health and the health of the baby,” said the study’s lead author, Stefanie Hinkle, an assistant professor of Epidemiology and Obstetrics and Gynecology at the university.
Hinkle was apparently referring to the guidelines regarding weight gain during pregnancy outlined by the Centre for Disease Control and Prevention (CDC) in the US, which recommend a weight gain of not more than 12.5-18 kg in ”underweight” women and 5-10 kg in ”obese” women. The ”Underweight” and ”obese” classifications are according to BMI standards. The CDC recommendations differ if a woman is pregnant with twins.
These days, almost half of those who are pregnant gain more weight than recommended, the researchers said in the study.
They examined data from the Collaborative Perinatal Project, which catalogued data from a racially diverse cohort of people in the US who gave birth in the 1950s or 1960s, and linked their records to mortality data that ran through 2016, approximately 50 years later.
The researchers analysed their BMI and weight gain data and compared them to modern recommendations. Those numbers were then linked first to deaths due to any cause, then to deaths caused by cardiovascular- or diabetes-related issues.
By 2016, approximately 39 per cent of the people in the cohort had died and the death rate varied in correlation with pre-pregnancy BMI – those with the lowest BMI died at a lower rate than those with the highest BMI, the researchers found.
They further found that for women ”underweight” before pregnancy, the risk of death related to heart disease climbed by 84 per cent when they gained more than the recommended weight.
Among those having a ”normal” BMI, death due to any reason rose by nine per cent and heart disease-related death risk climbed by 20 per cent, when their weight gain was more than that recommended, the researchers said.
Those ”overweight” had a 12 per cent higher risk of death and a 12 per cent increase in the risk of diabetes-related death, if they gained excess weight during pregnancy, they said.
However, the researchers found no correlation between high weight gain during pregnancy and subsequent deaths among those ”obese” before pregnancy.
Hinkle said while their study wasn’t designed to look into that specific point, it’s possible this group’s already-elevated death rate could have had a bearing on this finding.
The team also said while it is known that weight gain during pregnancy ”did not happen in a vacuum,” as health care access, nutrition, and stress significantly influenced it, they now had a better picture of the long-term risks associated with unhealthy weight gains and hope to find more that will help address the issue.