Researchers in New Zealand compared 84 first-time mothers who either exercised during pregnancy or were sedentary. The women who exercised participated in stationary cycling five times a week for 40 minutes. Those women gave birth to babies that were, on average, three to five ounces lighter than the babies of the non-exercisers. There was no difference in birth length between the two groups of babies. The exercise had no effect on maternal body mass index and no detrimental effect on insulin resistance. Previous studies have shown that exercise during pregnancy prevents excessive weight gain in women and can reduce the risk of gestational diabetes.
"Given that large birth size is associated with an increased risk of obesity, a modest reduction in birth weight may have long-term health benefits for offspring by lowering this risk later in life," the lead author of the paper, Dr. Paul Hofman, of the University of Auckland, said in a news release.
The study was released Monday online in the Journal of Clinical Endocrinology & Metabolism.
-- Shari Roan
Photo: Ricardo DeAratanha / Los Angeles Times