Obesity hurts a woman's chances of conception

Obesity hurts a woman's chances of conception
Overweight women walk across the street near Times Square in New York August 28 2007. Obesity decreases the chances that a woman will get pregnant, and the more obese she is, the worse her prospects of conception, Dutch researchers said on Tuesday. (Lucas Jackson/Reuters)CHICAGO (Reuters) - Obesity decreases the chances that awoman will get pregnant, and the more obese she is, the worseher prospects of conception, Dutch researchers said on Tuesday.
Researchers at the Academic Medical Center in Amsterdamlooked at how obesity affects women who are still ovulating buthaving trouble with conception.
The study, published in the journal Human Reproduction,included more than 3,000 couples between 2002 and 2004 in 24hospitals in the Netherlands.
Dr. Jan Willem van der Steeg and colleagues looked at therelationship between fertility in these women and their bodymass index, a ratio of weight to height. Women with a BMI of 30or higher are considered obese.
The women had to be ovulating and have at least one workingFallopian tube, and the men had to have a normal semenanalysis.
The researchers found that women with a BMI of 30 or higherhad significantly lower probability of becoming pregnantnaturally, compared with normal weight women who had BMIs ofbetween 21 and 29.
"In the case of a woman with a BMI of 35, the probabilityof spontaneous pregnancy was 26 percent lower, and in the caseof a woman with a BMI of 40, it was 43 percent lower," van derSteeg said in a statement.
One reason for this may be the hormone leptin, whichregulates appetite and energy expenditure and is secreted infatty tissues.
"It is possible that obese women may have disturbed hormonelevels, which decrease the chances of successful fertilizationand implantation," he said.
Obesity is already known to disrupt ovulation, and theDutch study now suggests it can lower pregnancy rates comparedwith women of normal weight.
However, the researchers did not track the timing andfrequency of sexual intercourse, which may have affected theresults. Some studies have shown that obesity is linked withless frequent sex and reduced sexual desire.
The researchers said the finding should be tested infurther studies, especially given the rising rates of obesity.
"Owing to the fact that more women of child bearing age arebecoming overweight and obese, this is a worrying finding,"they wrote.
(Reporting by Julie Steenhuysen; editing by MohammadZargham)