NEW YORK (Reuters Health) – New findings from The Netherlands provide more evidence that exercise interventions alone are not effective for reducing the risk of gestational diabetes in overweight pregnant women.
“It’s difficult to reach these women and get them to comply with such an intervention, which may explain our findings,” Dr. Mireille van Poppel of VU University Medical Center in Amsterdam, one of the study’s authors, told Reuters Health. “We need to look for other types of interventions to reach these women.”
Three previous studies of exercise interventions for preventing gestational diabetes mellitus (GDM) found that the programs reduced the rate of children born large for gestational age but did not affect mothers’ fasting blood glucose or GDM risk, Dr. van Poppel and her team wrote in the British Journal of Obstetrics and Gynecology, online May 23rd. However, dietary counseling has been shown to reduce GDM incidence, they add.
In the current study, the researchers looked at an intervention consisting of two weekly hour-long sessions including aerobic and strength training exercises. The 121 study participants were around 15 weeks pregnant, on average, at enrollment. The 59 who were assigned to the control group received normal care, while the other 62 received normal care plus the exercise intervention.
Up to 24 weeks’ gestation, 33.3% of the women in the exercise group attended at least half of the exercise sessions, while 11.1% did so from 24 weeks’ gestation to the end of their pregnancy. Overall, just 16.3% attended at least half of the exercise sessions throughout their pregnancy; this group was too small for per protocol analyses.
At baseline, women in the intervention group were spending a mean 202 minutes doing moderate to vigorous physical activity each week, while the control group women were spending 218 minutes. At 32 weeks’ gestation, average time spent in moderate to vigorous activity per week was 151 minutes for the intervention group and 178 minutes for the control group. Neither difference was statistically significant.
Intention-to-treat analyses found no effect of the exercise program on fasting blood glucose levels, insulin sensitivity, or birthweight.
A large, multi-center European study is now underway to investigate the effectiveness of an intervention consisting of counseling plus physical activity to prevent gestational diabetes, Dr. van Poppel noted. “We hope that compliance will be better and I think the combination of diet and physical activity is promising, based on the literature that’s available at the moment.”