Exploring the impact of pregnancy‑related weight gain

Pregnancy is a pivotal point in women’s lives that for some may literally tip the scales toward a less healthy future for both the women and their children. Particularly if women are already overweight at the beginning of pregnancy, PERU researchers have found they are more vulnerable to gaining more weight than recommended during pregnancy.

“We’ve found that 46 per cent of women in Nova Scotia are overweight or obese at the beginning of their pregnancy, and that 60 per cent gain more than the recommended amount of weight in their pregnancy,” says PERU epidemiologist Dr. Christy Woolcott. “Our analysis also shows that many women do not lose the extra weight post-partum, and end up accumulating weight from pregnancy to pregnancy.”

Pregnancy-related weight gain has serious implications for the immediate and long-term wellbeing of mother and child. As Dr. Woolcott explains, women who are overweight or obese during pregnancy face a higher risk of gestational diabetes and pre-eclampsia (pregnancy-related high blood pressure). They are also more likely to have complicated labour and require a caesarean section or other intervention to deliver the baby. Their babies are likely to be large for their gestational age and face an increased risk of growing up to be overweight, compared to the offspring of healthy-weight women.

But what is the effect of pregnancy-related weight gain on the future health of women? Dr. Woolcott and PERU colleagues Drs. Linda Dodds and Stefan Kuhle have joined forces with colleagues at Dalhousie University and the IWK to find out. They’re linking pregnancy data from the Nova Scotia Atlee Perinatal Database to comprehensive health data collected through the Atlantic PATH longitudinal cohort study, to see to what extent excessive pregnancy weight gain predisposes women to obesity, cardiovascular disease, diabetes and other chronic diseases later in their lives. The researchers hope their findings will give impetus to public and professional education programs aimed at ensuring women understand why it’s so important to enter pregnancy at a healthy weight and to avoid gaining too much during pregnancy.

“The national guidelines on gestational weight gain need to be communicated more clearly, so women understand how much they should gain at each stage of their pregnancy,” Dr. Woolcott says. “If they’re already obese at the outset of the pregnancy, they should gain very little throughout.”

Dr. Woolcott and colleagues in PERU and the Department of Obstetrics & Gynaecology are exploring the possibility of forming a large, multi-disciplinary research group to address the complex issues that surround pregnancy, overweight and obesity, and women’s and children’s health. “Our goal in PERU is to provide the evidence and a sense of urgency to support comprehensive efforts to change the culture in our society,” she says, adding that, “We need more emphasis on physical activity, as well as healthy eating, and we should be assessing women’s risk of chronic disease at a much younger age, so they have time to act to reduce their risk.”