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Small Changes Aid Birth Control Pill Effectiveness in Obese Women, Study Finds

Small Changes Aid Birth Control Pill Effectiveness in Obese Women, Study Finds

July 30, 2014 — Slightly increasing the dosage of birth control pills or continuously taking the pills without a weekly break each month can increase their efficacy in women who are obese, according to a new study in Contraception, the Portland Business Journal reports (Hayes, Portland Business Journal, 7/28).

According to Medical Xpress, previous studies have demonstrated that obesity has an adverse effect on drug levels in the body, meaning that birth control pills might not be as effective for obese women as they are for women of lower weights. The drugs take longer to reach a steady-state level in obese women, resulting in a greater risk of pill failure than lower-weight women experience if they forget or postpone taking a pill, Medical Xpress reports.

Study Results

Researchers at Oregon State University and Oregon Health & Science University explored how to address these changes and identified two strategies that appear to offset the effect obesity has on the drugs. They found that either increasing the dosage from a very low dose to a low dose or refraining from taking a week off -- when a pill user would normally menstruate -- appeared to counteract obesity's effect on the drugs.

Study co-author Alison Edelman, an associate professor of obstetrics and gynecology at Oregon Health & Science University, said, "[I]t's important to find methods of contraception that work for all women, no matter what their weight," given that birth control pills are among the most popular contraceptive methods in the U.S. and that "the majority of our population is obese or overweight" (Medical Xpress, 7/28).