Once pregnancy has been determined, you must be at less than 10 weeks gestation, to use the abortion pill. Beyond that point the effectiveness of the non-surgical procedure drops significantly. There are times that despite taking the pill, not all of the pregnancy tissue leaves the uterus. If this happens, you must have a surgical procedure. This only happens in about 5% of cases before 10 weeks of gestation. This is why we only occasionally provide the abortion pill in cases where a pregnancy is greater than 10 weeks.