Insufficient evidence for exercise preventing gestational diabetes mellitus

Clinical question: 
How effective is physical exercise for pregnant women for preventing glucose intolerance or gestational diabetes mellitus (GDM)?
Bottom line: 
Compared with routine antenatal care, exercise programmes, including individualised exercise with regular advice, weekly supervised group exercise sessions or home-based stationary cycling, either supervised or unsupervised, had no clear effect on preventing GDM or improving insulin sensitivity.
Caveat: 
None of the trials reported large-for-gestational age babies, perinatal mortality or long-term outcomes for women or their babies. No information was available on health service costs. All trials were conducted in high-income countries.
Context: 
GDM affects a significant number of women each year. GDM is associated with a wide range of adverse outcomes for women (type 2 diabetes mellitus) and their babies (birthweight >4kg and birth trauma). Recent observational studies have found physical activity during normal pregnancy decreases insulin resistance and therefore might help to decrease the risk of developing GDM.
Review CD#: 
CD009021
PEARLS No: 
371
Date: 
September, 2012
Authored by: 
Brian R McAvoy