Associations between high-volume exercise during pregnancy and birth outcomes: A systematic review

The safety of exceeding existing antenatal exercise volume recommendations is unclear. We synthesised the literature investigating associations between high-volume antenatal exercise and pregnancy outcomes.

Systematic review.

Eligible studies reported maternal or neonatal outcomes in participants who exercised for >900 MET-minutes·week^-1 during pregnancy, compared to those who engaged in lower volumes of exercise or did not exercise whilst pregnant. Database searches were conducted using CINAHL, MEDLINE Complete, Embase, Web of Science, SPORTDiscus, and the Cochrane Library in May 2023 and updated in November 2025.

Six studies were included in the analysis. 'Very low' certainty evidence (assessed using the Grading of Recommendations, Assessment, Development, and Evaluation approach) from four studies suggests that participants who engage in high-volume antenatal exercise may give birth to lighter infants than individuals who engage in lower volumes of exercise (mean difference range: -522 to -44 g) during pregnancy, although comparisons with people who do not exercise were inconsistent (mean difference range: -206.9 to 120 g). Few studies reported gestational age at birth (N = 2) or gestational weight gain (N = 3), or the incidence of low or high birthweight (N = 1), small or large for gestational age (N = 1), or preterm birth (N = 3) following exposure to high-volume antenatal exercise.

The clinical significance of the potential reduction in birthweight, as well as the associations between high-volume exercise and other pregnancy outcomes, remains unclear, highlighting the need for further research. This review was registered on the International Prospective Register for Systematic Reviews (PROSPERO; CRD42023427569).