The Effect of 12 Weeks Moderate Intensity Aerobic Exercise Training on Th1/Th2 Balance in the Second Trimester of Pregnancy

Immunological dysfunctions and imbalance of Th1 and Th2 cells in pregnant women can lead to adverse pregnancy outcomes. The effect of exercise training in changing immune-cell distribution during pregnancy is unclear. Therefore, this study was performed with aim to investigate the effect of 12 weeks moderate-intensity aerobic exercise training (AET) on Th1/Th2 (IFN-γ/IL-4) balance in the second trimester of pregnancy.

This semi-experimental study was conducted in 2022 on 30 pregnant women aged 20 to 35 years, with gestational age 12 to 15 weeks in Tabriz city. The subjects were randomly divided into two exercise and control groups. AET were performed according to the recommendations of the American College of Obstetricians and Gynecologists with moderate intensity (12-14 Borg RPE) for 12 weeks, 3 sessions per week and each session 45 min. The variables of weight, blood pressure, heart rate and serum levels of IL-4, IFN-γ were evaluated before and after the exercise protocol. The data were evaluated by SPSS software (version 25) and ANCOVA test. P<0.05 was considered statistically significant.

According to the results, the weight gain of the exercise group was significantly lower compared to the control group (P=0.027). Mean arterial blood pressure (P=0.019) and IFN-γ (P=0.025) were significantly decreased in the exercise group compared to the control group, but IL-4 and Th1/Th2 ratio did not show any significant difference (P>0.05).

In general, moderate intensity AET may be a safe way to improve the health of mothers in the second trimester of pregnancy, but considering limited studies and conflicting results, it seems that the effect of exercise training on Th1/Th2 balance in three different periods of pregnancy needs more investigations.