Excessive gestational weight gain (defined as weight gain above the Institute of Medicine guidelines), is becoming increasingly prevalent (1). It has been associated with increased risk of diabetes of pregnancy, persistent obesity in both mother & child, postpartum weight retention and increased cardiovascular morbidity & mortality. Excessive gestational weight gain is also associated with increased odds of babies born large for gestational age, macrosomia and caesarean section delivery (2). High quality evidence from a Cochrane review demonstrated significantly reduced excessive gestational weight gain, especially in women who underwent a supervised physical activity programme (3). Overall gestational weight gain was reduced by 20% (95%CI 11% to 30%); supervised interventions reduced gestational weight gain by 25% (7 studies, 15 to 41%) and unsupervised 17% reduction (3 studies; 3 to 39%). Physical activity interventions were also associated with lower mean gestational weight gain (mean difference -1.35kg, 95%CI -1.80 to -0.89kg).
A systematic review & meta-analysis of 84 studies reported 32% decreased odds of excessive gestational weight gain with physical activity interventions (15 RCTs, n=3519). They also report low to moderate-quality evidence that physical activity-only interventions were associated with a 1kg reduction in total gestational weight gain (28 RCTs, n=5819) and postpartum weight retention (3 RCTs, n=420) (4). Another meta-analysis of RCTs (n=3203, most including structured physical activity interventions) showed reduced gestational weight gain in women who were exposed to physical activity interventions in pregnancy, with a mean difference in gestational weight gain of -1.11kg (DSE -1.53; 0.69). The same group compared analysis of cohort studies (with self-reported physical activity data and more variable moderate-vigorous physical activity), reporting that women who were physically active during pregnancy had an 18% lower risk of excessive gestational weight gain compared with inactive women (OR 0.82, 95%CI 0.68 to 0.99) (5).
Weight retention between pregnancies is associated with maternal obesity, especially in overweight and obese women. These women are more likely to remain obese one year after giving birth, compared to women of normal weight. Increased BMI between pregnancies is associated with significantly higher maternal and fetal/neonatal complications in subsequent pregnancies (2). Prenatal physical activity interventions reduced gestational weight gain for overweight and obese pregnant women (13 studies, n=1439; mean difference -1.14kg, 95%CI -1.67 to -0.62, p<0.0001). Physical activity-only interventions reduced gestational weight gain by 1.3kg in overweight and obese pregnant women (6). The LIFE-Moms prospective meta-analysis demonstrated that excessive gestational weight gain was significantly lower in women with BMI [Symbol]25m2 randomised to a lifestyle intervention group (61.8% vs. 75.0% in those not allocated to the intervention group, OR 0.52, 95%CI 0.40 to 0.67). Total gestational weight gain was lower in the intervention group (8.1 +/- 5.2 vs 9.7 +/- 5.4kg; mean difference -1.59kg, 95%CI -2.18 to -0.99kg) (7). These findings are in contrast to another group reporting on physical activity-only interventions, which showed a small but non-significant pooled effect size in reducing gestational weight gain (6 RCTs, -0.28kg weight gain difference). However, all of the included studies involved less than 100 participants, and adherence was low, possibly underestimating the effect of these interventions (8).
The effectiveness of physical activity interventions on gestational weight gain is related to adherence and compliance, especially in overweight and obese women. Recommendations include that to achieve at least a 25% reduction in odds of excessive gestational weight gain, women need to accumulate at least 456 metabolic equivalent (MET)-min/week of moderate intensity activity, or at least 2 sessions/week of at least 35mins/session (5).
Quality of evidence
Strength of recommendation
Physical activity in pregnancy reduces both overall and excessive gestational weight gain in pregnant women, including those of normal weight and those who are overweight/obese. Supervised activity interventions are particularly effective in reducing gestational weight gain.
1. McDonald SM et al. Does dose matter in reducing gestational weight gain in exercise interventions? A systematic review of literature J Sci Med Sport 2016 Apr;19(4)323-35
2. Dalrymple KV et al. Lifestyle Interventions in Overweight and Obese Pregnant or Postpartum Women for Postpartum Weight Management: A Systematic Review of the Literature Nutrients 2018 Nov 7;10(11)
3. Muktabhant B et al. Diet or exercise, or both, for preventing excessive weight gain in pregnancy Cochrane Database Syst Rev. 2015 June 15;(6):CD007145
4. Ruchat S-M, Mottola MF, Skow RJ et al. Effectiveness of exercise interventions in the prevention of excessive gestational weight gain and postpartum weight retention: a systematic review and meta-analysis Br J Sports Med 2018;52:1347-1356
5. da Silva SG et al. Leisure-Time Physical Activity in Pregnancy and Maternal-Child Health: A Systematic Review and Meta-Analysis of Randomised Controlled Trials and Cohort Studies Sports Med 2017 Feb;47(2):295-317
6. Du MC et al. Effects of physical exercise during pregnancy on maternal and infant outcomes in overweight and obese pregnant women: A meta-analysis Birth 2018 Sep 21
7. Peaceman AM et al. Lifestyle Interventions Limit Gestational Weight Gain in Women with Overweight or Obesity: LIFE-Moms Prospective Meta-Analysis Obesity (Silver Spring) 2018 Sep;26(9):1396-1404
8. Shieh C et al. Intervention strategies for preventing excessive gestational weight gain: systematic review and meta-analysis Obes Rev 2018 Aug;19(8):1093-1109