Physical activity and fertility

BACKGROUND: Before pregnancy is recognized, ovulation, fertilization, and implantation must all occur. Physical activity and sedentary behavior may impact pregnancy success by altering each or all of these processes. The aim of this review was to review the association between physical activity and sedentary behavior with spontaneous female and male fertility. METHOD: PubMed/MEDLINE, Web of Science, CINAHL, SPORTDiscus, and Embase were searched from inception to August 9, 2021. Eligible studies included randomized controlled trials or observational studies, published in English, describing an association between physical activity or sedentary behavior (exposures) and spontaneous fertility (outcome) among females or males. RESULTS: Thirty-four studies from 31 unique populations were included in this review (12 cross-sectional studies, 10 cohort studies, 6 case control studies, 5 randomized controlled trials, and 1 case cohort study). Of the 25 studies among females, the majority identified mixed results (n=11) or no association (n=9) between physical activity and female fertility. Seven studies reported on female fertility and sedentary behavior, 2 found sedentary behavior was associated with decreased female fertility. Of the 11 studies among males, most of the studies (n=6) found physical activity was associated with increased male fertility. Two of the studies reported on male fertility and sedentary behavior, neither identified an association. CONCLUSIONS: The association between spontaneous fertility and physical activity in both males and females remains unclear, while the association with sedentary behavior remains largely unexplored.