Exercise versus Metformin to Improve Pregnancy Outcomes among Overweight Pregnant Women: A Systematic Review and Network Meta-Analysis

Abstract

Being overweight is associated with pregnancy-related disorders such as gestational diabetes mellitus (GDM), hypertensive disorders of pregnancy (HDP), and excessive maternal weight gain (MWG). Exercise and metformin reduce the risk of these disorders. This network meta-analysis (NMA) aims to compare the effect of metformin and different types of exercise (aerobic, resistance and combined) on the risk of GDM, HDP, and MWG among overweight/obese pregnant women. Medline, EMBASE, Web of Science and Cochrane Library were searched from inception to June 2021. Meta-analyses and NMAs were performed. Sixteen randomized controlled trials were included. In the NMA, aerobic exercise showed an effect on GDM (RR = 0.51, 95% CI = 0.26, 0.97), and metformin a reduction in MWG (MWG = −2.93 kg, 95% CI = −4.98, −0.87). No intervention showed any effect on the reduction of HDP. Our study suggests that aerobic exercise may have the greatest effect in reducing the risk of GDM, and perhaps, the MWG. Strategies should be developed to increase adherence to this type of intervention among overweight women without contraindications. Although metformin could reduce MWG, medicalization of pregnancy in healthy women is not justified with the present results. More research is needed on the effect of the intensity and frequency of exercise sessions and the length of interventions.

Effect of Home-Based Tele-Pilates Intervention on Pregnant Women: A Pilot Study

“…Increased anxiety and stress in potential mothers can cause side effects such as nausea, vomiting, loss of weight, and depression. These, in turn, can induce diabetes, hypertension, and obesity [ 9 ]. A previous study has reported a two-fold increase in anxiety disorders in pregnant women after COVID-19.…”

Physical Exercise vs. Metformin to Improve Delivery- and Newborn-Related Outcomes Among Pregnant Women With Overweight: A Network Meta-Analysis

“…Considering that body mass index is associated with birth weight and risk of cesarean section, the hypothesis that obesity and excessive maternal weight gain increases the deposition of fatty tissue in the maternal pelvis and increases birth weight, causing obstructed labor, is attractive ( 58 ). This hypothesis is supported by the reduction of maternal weight gain with metformin ( 19 ). However, in the meta-regressions, no association was observed between the maternal weight gain and the risk of cesarean section.…”

“…Fourth, metformin had no effect on the risk of macrosomia, which was interesting, but it did have a significant effect on the risk of cesarean section. Since metformin could have some effect on maternal weight gain and cesarean section, and it appears to be safe for newborns ( 19 , 56 ), its use in specific cases and with a thorough assessment of the benefit-risk profile cannot be ruled out. However, the lack of effect on other outcomes, the low quality of the evidence (GRADE) and the caution in the administration of drugs during pregnancy do not allow to recommend a generalized medicalization of healthy pregnant women with obesity.…”

“…In a previous network meta-analysis ( 18 ), metformin reduced the risk of cesarean section. Moreover, a previous network meta-analysis by our group ( 19 ) showed that the type of exercise (i.e., aerobic, resistance, or combined) could determine the effect obtained, as observed with aerobic exercise and the risk of gestational diabetes mellitus. Therefore, the aim of this systematic review and network meta-analysis is to estimate the effect of metformin and different types of exercise on the development of delivery and newborn complications, including the risk of cesarean section, preterm birth, macrosomia, and birth weight among pregnant women with overweight/obesity.…”

Metformin: Sex/Gender Differences in Its Uses and Effects—Narrative Review

“…The incidence of cardiovascular events in women on MTF has been found to be lower to that of men on MTF. Despite some promising results with MTF regarding pregnancy rates in women with PCOS, for the management of gestational diabetes, cancer prevention or adjunctive cancer treatment and COVID-19, data from the most robust meta-analyses of clinical studies have yet to confirm such beneficial effects [ 35 , 38 , 132 , 133 , 134 , 135 , 136 , 137 , 138 , 139 , 140 , 141 , 142 , 143 , 144 , 145 , 146 ]. A caveat is that any extrapolation of benefit to humans from animal or in vitro studies has to take into account the level of MTF concentration attained; the latter may differ considerably and be lower in humans [ 147 ].…”