The effects of a supervised exercise training program during pregnancy on placental cytokines, and the potential role of fetal sex and maternal weight status.

Background: The mechanisms underlying the beneficial effects of exercise on the human placenta are poorly understood. The objective of the current study is to ascertain the influence of a supervised concurrent exercise intervention from gestational week 17 until birth on key cytokines involved in placental development and function. Secondary aims were to explore: (a) the moderating effects of fetal sex and maternal weight status; and (b) whether gestational weight gain, lifestyle behaviors (diet, sleep patterns, and physical activity), and physical fitness (strength and cardiorespiratory fitness) mediated the effects of exercise on placental cytokines.

Methods: Seventy-six pregnant women (33 ± 4 years, mean ± SD), divided into exercise (n = 40) and control (n = 36) groups, participated in this study. The exercise group followed a 60-min, 3 days/week (aerobic + resistance) training program of moderate-to-vigorous intensity. Placental cytokines-including granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF), platelet-derived growth factor AA (PDGF-AA), epidermal growth factor (EGF), monocyte chemoattractant protein-1 (MCP-1), fractalkine, interleukin (IL)-8, IL-6, IL-1β, IL-1ra, IL-10, tumor necrosis factor alpha (TNF-α), and interferon gamma (IFN-γ) were analyzed using Luminex multi-analyte profiling (xMAP) technology.

Results: The exercise group presented higher placental levels of G-CSF and lower concentrations of EGF and IL-1ra than the control group (p < 0.05). Significant effects of exercise on placental G-CSF and TNF-α (p < 0.05) and a trend toward lower IL-6 (p = 0.08) were observed only in female placentas. Additionally, a reduction in weight gain partially mediated the effects of exercise on G-CSF (p < 0.05).

Conclusion: Maternal exercise during pregnancy is related to increased placental levels of G-CSF and lower EGF and IL-1ra levels. Some exercise-induced effects are observed exclusively in female placentas, including increased G-CSF and lower TNF-α and IL-6 concentrations. Notably, the increased levels of G-CSF observed with exercise might be due to a more adequate gestational weight gain.