Moderate exercise during pregnancy can decrease the risk for gestational diabetes by 31% and also can reduce maternal weight gain, according to a meta-analysis of randomized controlled trials published online June 3 in the British Journal of Obstetrics and Gynecology.
“Exercise is not something to be feared during pregnancy — the moderate levels of exercise used in these studies had significantly positive effects on health and were found to be safe for both mother and baby,” lead author Gema Sanabria-Martinez, MSc, from Virgen de la Luz Hospital in Cuenca, Spain, said in a journal news release.
Gestational diabetes, a common complication during pregnancy, is linked to more serious problems, such as preeclampsia, hypertension, premature birth, higher rates of caesarean delivery, and later type 2 diabetes in the mother. Children born to women with gestational diabetes also have a higher risk of developing type 2 diabetes and obesity later in life.
Excessive weight gain during pregnancy poses similar health risks. Women with excessive weight gain may also have difficulty losing the weight after pregnancy, increasing their risk for obesity.
Traditional wisdom has held that women should reduce their physical activity, or stop exercising altogether, during pregnancy. Recent research, however, has suggested that exercise during pregnancy could improve outcomes in the mother and child. The American College of Obstetricians and Gynecologists currently recommends that pregnant women engage in moderate exercise at least 30 minutes per day on most days of the week. Studies have conflicted, though, on whether exercise during pregnancy can decrease gestational diabetes and improve maternal weight gain, the authors write.
For the meta-analysis, the authors searched six scientific databases for randomized controlled trials published in English or Spanish between January 1990 and May 2014. Included trials evaluated exercise programs for healthy pregnant women who were sedentary or had low exercise levels at the start of the studies. The exercise programs varied widely in type, frequency during a week, and overall duration; some programs started in the second trimester, whereas others spanned the entire pregnancy.
The analysis included 13 randomized controlled trials, covering 2873 pregnant women. Results showed that pregnant women who engaged in exercise programs decreased their risk for gestational diabetes by 31% (relative risk [RR], 0.69; 95% confidence interval [CI], 0.52 – 0.91; P = .009). Women who exercised during their entire pregnancy did even better, with a 36% decreased risk for gestational diabetes (RR, 0.64; 95% CI, 0.36 – 0.98; P = .038). Engaging in combined exercises such as toning, strengthening, flexibility, and aerobic exercises lowered the risk for gestational diabetes by 31% (RR, 0.69; 95% CI, 0.48 – 0.99; P = .043).
In addition, women who exercised during pregnancy gained about 1 kg less than those who did not (weight mean differences [WMD], −1.14 kg; 95% CI, −1.50 to −0.78; P < .001). There was no substantial difference in terms of reduced weight gain between exercising throughout pregnancy versus from the second trimester on (WMD, −1.16 kg [95% CI, −1.47 to −0.85; P < .001]; WMD, −1.03 kg [95% CI, −1.48 to −0.59; P < .001], respectively).
Women who exercised during pregnancy did not experience any adverse effects related to exercise.
“[O]ur study has important clinical and public health implications, because it provides support for the recommendation to advise mothers to engage in [physical activity] programmes as an effective and safe strategy to experience healthier pregnancies,” the authors conclude. “[T]hey will have less risk of [gestational diabetes] and they will avoid excessive weight gain and, as a consequence, improve the health status of their offspring.”
The authors have disclosed no relevant financial relationships.
BJOG. Published online June 3, 2015. Abstract
— Veronica Hackethal, MD