For how we live.
Trials put the pregnancy rate after emergency contraceptive pills at roughly 1-3%. But the risk rose more than threefold in obese women, and the levonorgestrel pill fared worst of all.
In a study of 543,167 cycles, calendar-based apps misclassified a fertile day as safe in two-thirds of cycles. Apps that track a real biological signal do better, but plain calendar apps remain the most common kind.
In a 22,785-user study of one temperature-based app, typical use failed 6.9 per 100 woman-years and perfect use 1.0 — but the study came from the maker, and traditional methods vary widely.
A million-woman Danish cohort found a modest rise in antidepressant use among hormonal contraceptive users. A Cochrane review of weight found no evidence the pill causes weight gain.
The numbers most methods advertise are perfect-use figures from clinical trials. In everyday use the pill fails about seven users in 100 a year, the condom about 13, withdrawal about 20.
A national pharmaceutical database analysis found out-of-pocket purchases accounted for 78-86% of contraceptive use, with emergency contraception priced up to 25 times higher than the insured rate.