Several new studies have shown that the use of the Pill as a birth control method might be less effective in obese women.
The studies, which took place at the Bellevue Hospital Center in New York, showed that women with a body mass index (BMI) in the overweight range (a BMI of 25 or more) had a higher risk of pregnancy than those in the normal weight range, despite the fact that they were using oral contraceptive pills.
Dr. Amitasrigowri Murth, who directs the reproductive choice program at the New York hospital said the results were worrying, particularly in light of the recent U.S obesity epidemic.
"Women who are obese or overweight also should consider potential health risks from hormonal contraceptives," said Dr. Murth.
The situation isn’t as simple as once thought, however. Dr. Murth said that there are discrepancies in the study. "BMI is thought to be an indicator of how much fat a person has, while body weight reflects the overall body size. So currently, the evidence that extra fat reduces the effectiveness of oral birth control is limited", he said.