The effects of high intensity exercise on pregnancy outcomes and complications during pregnancy: a meta-analysis of randomized controlled trials

Abstract

Background: There is a strong correlation between the level of physical activity undertaken during pregnancy and the health of both the mothers and the fetus. The physical activity guidelines for pregnancy recommend moderate to high-intensity exercise, yet in practice, few pregnant women currently engage in high-intensity exercise, and there is no consensus on its effect on pregnancy outcomes. The objective of this meta-analysis was to investigate the effects of high-intensity exercise on pregnancy outcomes and pregnancy complications in healthy pregnant women.

Methods: Electronic searches of the Cochrane Library, PubMed and Web of Science were conducted from the inception of the databases to 21 December 2023. The search used a range of relevant terms "pregnancy" "gestation" " physical activity" "exercise" to capture all potentially eligible results relating to exercise interventions during pregnancy. A total of 16 RCTs were analyzed. The indicators analyzed are GWG, EGWG, BW, LBW, VO₂/AT, Apgar score 1 and 5 min after birth, GDM, PIH.

Results: High-intensity exercise during pregnancy can effectively reduce the incidence of GDM compared to the control group (OR = 0.45, 95% CI = 0.30, 0.68, P = 0.0001). It also improves the 5-min Apgar score of newborns (MD = 0.09, 95% CI = 0.06, 0.12, P < 0.00001), and although the 1-min Apgar score was also improved, it was not significant (MD = 0.13, 95% CI = 0, 0.27, P = 0.05). In addition, pregnant women who performed high-intensity exercise during pregnancy had a much smaller rate of change of VO₂/AT than the control group (MD = 3.37, 95% CI = 1.25, 5.49, P = 0.002). However, there were no significant differences in the preterm birth rate (OR = 0.95, 95% CI = 0.58, 1.55, P = 0.83), gestational week of delivery (MD = 0.04, 95% CI = - 0.12, 0.20, P = 0.62), prevalence of GWG (MD = - 0.91, 95% CI = - 1.96, 0.14, P = 0.09), EGWG (OR = 0.98, 95% CI = 0.47, 2.03, P = 0.95), BW (MD = - 33.19, 95% CI = - 84.72, 18.34, P = 0.21), LBW (OR = 2.44, 95% CI = 0.81, 7.29, P = 0.11) and prevalence of PIH (OR = 0.6, 95% CI = 0.31, 1.17, P = 0.14) between high-intensity exercise group and control group.

Conclusions: The study suggests that performing high-intensity exercise during pregnancy does not have adverse effects on pregnancy outcomes for healthy pregnant women. In addition, it reduces pregnancy complications and reduces the risk of developing gestational diabetes. The rate at which maximum sustained exercise capacity decreases is delayed or remains unchanged. These findings can assist pregnant women in selecting a suitable exercise intensity during pregnancy and provide a scientific basis for physicians to prescribe high-intensity exercise.

Trial registration: PROSPERO trial registration CRD42024503843.

Keywords: Gestation; Gestation weight gain; Gestational diabetes; High-intensity exercise; Infant; Pregnancy; Premature birth.