How does emergency contraception prevent pregnancy?
Researchers have identified several ways that hormonal emergency contraceptive pills (also called “morning after pills” or “day after pills”) likely prevent pregnancy. How they might work in your case depends on where you are in your monthly menstrual cycle when you use them. But no matter when you take emergency contraception, it will not cause an abortion. For more about how EC works, read this article in Journal of the American Medical Association. Studies show that both progestin-only and combined emergency contraceptive pills can prevent or delay ovulation (the time in your cycle when your ovaries release an egg). If you take emergency contraceptive pills before fertilization (the point when the egg and sperm meet), they may interfere with the process of fertilizing the egg, for instance making it harder for the egg or the sperm to travel (and meet up) in your reproductive tract. It’s also possible that emergency contraceptive pills work after fertilization, making it impossible f
ECPs—like all regular hormonal contraceptives such as the birth control pill, the implant Implanon, the vaginal ring NuvaRing, the Evra patch, and the injectable Depo-Provera1, and even breastfeeding—prevent pregnancy primarily, or perhaps exclusively, by delaying or inhibiting ovulation and inhibiting fertilization. We can’t always completely explain how contraceptives work, and it is possible that any of these methods may at times inhibit implantation of a fertilized egg in the endometrium. But the best evidence that we have suggests that levonorgestrel and ulipristal acetate ECPs do not interfere with post-fertilization events. For more about how EC works, read this. The Copper-T IUD does not affect ovulation, but it can prevent sperm from fertilizing an egg. It may also prevent implantation of a fertilized egg. Emergency contraceptive pills will not cause an abortion. Hormonal emergency contraceptive pills are not the same as the abortion pill. There is no time when the emergency c
Emergency contraceptive pills—like all regular hormonal contraceptives such as the birth control pill, the implant Implanon, the vaginal ring NuvaRing, the Evra patch, and the injectable Depo-Provera1, and even breastfeeding—prevent pregnancy primarily, or perhaps exclusively, by delaying or inhibiting ovulation and inhibiting fertilization. We can’t always completely explain how contraceptives work, and it is possible that any of these methods may at times inhibit implantation of a fertilized egg in the endometrium. But the best evidence that we have suggests that levonorgestrel and ulipristal acetate EC does not interfere with post-fertilization events. For more about how EC works, read this. The Copper-T IUD does not affect ovulation, but it can prevent sperm from fertilizing an egg. It may also prevent implantation of a fertilized egg. Emergency contraceptive pills will not cause an abortion. EC is not the same as the abortion pill. There is no time when the emergency contraceptive
