Trying to get pregnant? Vigorous exercise could hurt your chances

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By Catherine Holland By Catherine Holland

PHOENIX -- According to a new study, moderate exercise might help women who are considered normal weight get pregnant faster. It's a fine line, though, because vigorous exercise can delay pregnancy for all women except those who are considered overweight or obese.

Fertility specialist Dr. Drew Moffit of Arizona Reproductive Medicine Specialists explained it to Kaley O'Kelley, pointing out that the more than 3,600 women who took part in the study were recruited from the general population, not from infertility patients.

Moffit, who has experienced infertility treatment with his wife, said the results of the study were stunning.

It found that as little as two hours of vigorous exercise a week could reduce a woman's chance of getting pregnant if she was considered normal weight, which is  a body-mass index of 25 or less. That was not the case with women considered overweight or obese.

"These findings indicate that physical activity of any type might improve fertility among overweight and obese women, a subgroup at higher risk of infertility," wrote study author Lauren Wise, an associate professor of epidemiology at Boston University School of Public Health. "Lean women who substitute vigorous physical activity with moderate physical activity may also improve their fertility. "

According to Moffit, vigorous physical activity includes running, fast cycling, swimming and aerobics -- exercise that significantly increases the heart rate. Moderate exercise included activities like brisk walking, leisurely cycling and golf.

"We're going to have to have a different message," Moffit said. "the bottom line is if you're normal weight, vigorous exercise [is] probably not a good idea. If you're overweight, vigorous exercise or moderate is fine."

Moffit can be reached at 602-343-2767 or by visiting Arizona Reproductive Medicine Specialists is located at 1701 E. Thomas Road in Phoenix.