by Bianca Garilli, ND
Increased gestational weight gain (GWG) is of major concern due to its potentially negative impact on a mother’s long term health as well as the health of her newborn. Maternally, raised GWG is associated with postpartum weight retention and obesity later in her life; it may also lead to complications of pregnancy including pre-eclampsia, gestational diabetes and an increased risk of cesarean birth. Children born to increased GWG mothers may have higher birthweights potentially leading to a higher risk of overweight and obesity in childhood and adolescence.1 Research indicates a three-fold increase in overweight at ages 1 and 3 for vaginally delivered children born to overweight mothers when compared to infants born vaginally to normal weight mothers and there was a five-fold risk for 1 and 3 year old children if born to overweight mothers undergoing a cesarean birth.2
Preventing high GWG increases the likelihood of reducing risk for subsequent maternal and child health issues. Interventions to limit unhealthy weight gain while still supporting adequate weight gain for a healthy pregnancy may improve overall outcomes for the mother-child pair. A randomized controlled trial published in the International Journal of Obstetrics and Gynaecology examined whether a lifestyle intervention during pregnancy would limit the GWG and provide measurable health benefits for the mother and child. 1
Six hundred and six healthy, non-diabetic women with a BMI ≥ 19 were randomized into either an intervention group (who received dietary counselling twice by telephone and access to twice-weekly exercise groups over the course of their pregnancy) or to a control group (who received standard prenatal care). Participants were measured at three separate points during pregnancy as well as at delivery. Newborns were measured upon delivery. Results from the study indicated that the mean GWG from pre-pregnancy weight in the intervention groups was 14.4 kg (31.68 lbs) and 15.8 kg (34.76 lbs) for the control group. 1
Although the study found there to be a modest but significant decrease in GWG in the intervention group, there was no decrease in the incidence of pregnancy complications and no effect on fetal weight or neonatal outcomes. Additional limitations to the study may help to understand the results more clearly including:
- Very few women in the study were overweight or obese prior to pregnancy
- Pre-pregnancy weight was self-reported
- Many women from both groups in the study attended the same clinic and may have shared conversations and influenced one another regarding activities and interventions and affected study results
Additional studies utilizing mothers who are overweight and obese prior to pregnancy, and implementing interventional recommendations which are considerably different from the control group may offer further information into this extremely important and complex topic.
Why is this Clinically Relevant?
- Lifestyle interventions to support a healthy GWG may improve long term health outcomes for mothers and their children
- Optimizing maternal BMI prior to conception is an important part of reducing the risk for pregnancy and infant health complications
- All women during childbearing years should focus on maintaining a healthy BMI for their health and their future children; preventive education during annual health checkups is an excellent time for such conversations
1. Sagedal LR et al. Lifestyle intervention to limit gestational weight gain: the Norwegian Fit for Delivery randomised controlled trial. BJOG 2017;124:97–109.
2. Tun HM et al. Roles of birth mode and infant gut microbiota in intergenerational transmission of overweight and obesity from mother to offspring. JAMA Pediatr. 2018;172(4):368-377.