Women who gain too much weight during pregnancy may face a higher risk of developing life-threatening complications, a new study suggests. According to the study led by McMaster University researchers, weight gain that exceeded the recommended amounts was associated with potential health problems, which include infections, excessive bleeding, cardiovascular disease and kidney disease. The findings, published in JAMA Network Open on Thursday, were based on more than one million births in Ontario between 2012 and 2022. From the total pregnancies studied, nearly 53 per cent of women gained more weight than recommended. “We found that maternal pregnancy complications are a significant public health issue, and we need to do more to prevent them,” Laura Anderson, the study’s principal investigator and associate professor with McMaster University’s Department of Health Research Methods, Evidence and Impact, said in a video interview with CTVNews.ca from Hamilton, Ont. Researchers found that the risk is elevated, regardless of the individual’s body mass index (BMI) level and weight before the pregnancy. The BMI – a ratio of weight-to-height – is divided into ranges associated with health risk. Current clinical guidelines for weight gain during pregnancies vary, depending on the individual’s BMI at the start of the pregnancy, Anderson said. Doctors may recommend that women with higher BMI gain less weight during pregnancy than those whose BMI is lower, she added. ‘Unexpected complications’ Researchers used data from the Better Outcomes Registry & Network (BORN) Ontario. Among the pregnancies, they found more than 15,000 severe maternal morbidity cases. According to the study, severe maternal morbidity refers to “unexpected complications” that may result in “serious consequences” for a pregnant woman. But weight isn’t the only factor in potential complications. The risk of “severe” maternal complications is even higher – about double – for those with high blood pressure, asthma, diabetes or other pre-existing conditions, according to researchers. The higher risks for potentially severe health complications were even associated with those who gained less than the recommended amount of weight in some cases, including those with pre-existing medical conditions. Dr. Kaberi Dasgupta, a senior scientist and professor of medicine at McGill University who was not involved with the study, said the findings highlight the problem with weight gain and the need to support pregnant people. “Pregnancy is a really important time to understand the future risks for moms and babies, but also the ongoing risks,” Dasgupta said in a video interview with CTVNews.ca. “Understanding the role of weight gain in pregnancy is quite important, because then it increases the priority for pregnant people, their families, their health-care providers and society.”
