Miscarriage risk higher in overweight women

California, November 15: Overweight or obese women are at significantly increased risk of miscarrying a healthy baby than women of a normal weight, suggests a new study.

According to the novel study, carried out by Stanford University School of Medicine in California, slightly overweight women are more likely to miscarry healthy babies than those who are thinner.

The study looked at the relationship between body mass indexdefine (BMI) and miscarriage risk among women.

A team of researchers, led by Dr Inna Landres, reached their findings after studying 204 fertility clinic patients with an average age of 34 whose fetuses were miscarried in the first eight weeks of pregnancy.

After analyzing DNA from miscarried fetuses, the researchers found that expectant mothers with a body mass index of between 25 and 30 were nearly 50 percent more likely to miscarry a healthy baby than lighter women.

Dr Landres’ team found that 53 per cent of fetuses miscarried by overweight women were normal with no chromosome complications that cause between 50 to 70 per cent of miscarriages compared with 37 percent of babies that were miscarried by slimmer women.

"Obesity predisposes women to miscarry normal babies. We found women with a BMI of 25 or more were more likely to miscarry normal embryos," said Dr Landres, who presented the study results at the American Society for Reproductive Medicine conference in San Francisco.

"The excess miscarriage rate in overweight and obese women is due to the loss of chromosomally normal embryos," she added.

American Obesity Association (AOA) has described the obesity on its website as a complex, multi-factorial chronic disease involving environmental (social and cultural), genetic, physiologic, metabolic, behavioral and psychological components. It is the second leading cause of preventable death in the United States.

Today, obesity has become a burning issue in many of the countries, mostly in the developed ones. It has reached almost epidemic levels in the United States where, as of November 2007, nearly 127 million adults are overweight, 60 million obese and 9 million severely obese.

"It's important to identify elevated BMI [body mass index] as a risk factor for miscarriage and counsel those women who are affected on the importance of lifestyle modification," Dr Landres concluded.

From the clinical point of view, obesity is typically evaluated by measuring BMI (Body Mass Index), waist circumference, and evaluating the presence of risk factors and comorbidities.

According to the latest guidelines, a BMI less than 18.5 is regarded as ‘underweight’; a BMI between 18.5 - 24.9 is considered ‘normal weight’; a BMI between 25 and 29.9 is regarded as overweight; a BMI between 30 and 39.9 is considered obese and a BMI of 40 or higher is regarded as ‘severely (or morbidly) obese’.