By IANS,
Washington: Hormonal contraceptives seem to be less effective in preventing pregnancy among obese or overweight women, a study says.
Four of seven studies examined in a review comprising 39,531 women suggest that the heaviest women have the highest risk of pregnancy while using the contraceptives.
“Obese or overweight women should also consider potential health risks from hormonal contraceptives,” said Amitasrigowri Murthy, who directs the reproductive choice programme at Bellevue Hospital Centre in New York, reports The Cochrane Library.
“Some studies show that estrogen-based contraceptives can increase the risk of heart attack, blood clots, high blood pressure and gallbladder disease in obese women, who are already at increased risk for these conditions,” Murthy said.
In a study of oral contraceptive pills, women with a body mass index (BMI) – height to weight ratio – in the overweight range had a higher risk of pregnancy that those in the normal weight range, says a release of Family Health International (FHI) – a global health and development organisation.
“Other contraceptives such as injectable or implantable hormones might be unaffected by body mass,” said study lead author Laureen Lopez of Family Health International.
Many researchers think that metabolic changes associated with obesity – in particular, the amount of body fat – could make hormonal birth control less effective.
“However, we know little about how overweight women metabolise hormonal contraceptives since many studies exclude overweight women,” Lopez added.