Physical Activity during Pregnancy and Newborn Body Composition: A Systematic Review

Abstract

The current literature demonstrates that not only is exercise during pregnancy safe, but it has substantial maternal and infant benefits and appears to influence infant growth/size throughout pregnancy and at birth. However, many existing studies have investigated only the effects of prenatal exercise on birth weight. The purpose of this review was to determine the impact or association of maternal physical activity during pregnancy on neonatal body composition assessed between birth and two weeks of age. Electronic database searches were conducted on 29 July 2019 for randomized control trials and cohort studies, with an updated search completed on 8 January 2021. A total of 32 articles that met eligibility criteria were selected for review. Overall, prenatal exercise was not associated with infant body composition at birth. Yet, five of the studies identified suggest that infant body composition could be influenced by higher volumes of mid-to-late term prenatal physical activity. This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered in PROSPERO (Registration No. CRD42020160138).

Guidelines for Prenatal and Postpartum Resistance Training

“…Prenatal exercise has a plethora of benefits for both pregnant women and the fetus(es) they carry. Exercise during pregnancy has been shown to increase the incidence of vaginal delivery as well as lower the incidence of cesarean delivery, excessive gestational weight gain, gestational diabetes, gestational hypertensive disorders, preterm birth, and lower birth weight [1][2][3][4][5][6]. Additionally, prenatal exercise has a positive impact on healthy growth and improved cognition and intelligence of the baby after birth [3].…”

“…Moderate-intensity exercise training during pregnancy is associated with a lower incidence of gestational diabetes and reduced maternal weight gain [3,6,13,14]. Prenatal physical activity yields the best results in managing gestational diabetes and maternal weight gain when performed in a combination aerobic and resistance training.…”

“…Historically, pregnant and postpartum women have been discouraged and even advised against partaking in physical activity for fear of harming or terminating their pregnancy [1]. With an explosion of research in prenatal and postpartum exercise in the last decade, not only has the myth that physical activity causes miscarriage been disproven, evidence to support prenatal and postpartum exercise as a contributing factor to improved maternal and fetal health has emerged [1][2][3][4][5][6]. Adherence to guidelines for prenatal and postpartum exercise, including resistance training, can ensure safe and active pregnancies and restorative postpartum recoveries.…”

Influence of Physical Activity during Pregnancy on Birth Weight: Systematic Review and Meta-Analysis of Randomized Controlled Trials

“…However, associations between physical activity in pregnancy and birth weight have been inconclusive. For example, a recent systematic review of 32 studies on prenatal physical activity concluded that there is no association between engagement in physical activity throughout pregnancy and newborn body composition markers [ 18 ]. Another study that included objective measures of prenatal physical activity via accelerometry suggested that physical activity was correlated with birth weight, and specifically, that aerobic activity reduced birth weight and increased the number of newborns weighing within the appropriate range [ 19 ].…”