Several ways to prevent pregnancies exist such as oral contraceptives, condoms and injected contraceptives. However, if the contraceptive fails (a condom breaks) or if no contraception was used in the first place and a pregnancy is undesirable, then morning after pills come into the picture.
Emergency contraceptive pill are available over the counter for women of 18 years age or older.
To understand how a morning after pill works, you need to first, try to understand the female reproductive cycle.
The menstrual cycle involves many hormones and the female reproductive system is very complicated.
The pituitary gland of a woman secretes Follicle Stimulating Hormone shortly after the commencement of her periods. The function of this hormone is to instruct the ovaries to prepare a follicle for ovulation.
After a follicle develops, it starts producing the hormone estrogen. Estrogen thickens the lining of the uterus and prepares it to accept a fertilized egg. Before ovulation, the ovaries start secreting the hormone progesterone.
When the level of estrogen in the blood is high enough, the pituitary gland releases Luteinizing Hormone (LH). This hormone causes the follicle to release the egg into the fallopian tube. If a sperm manages to successfully fertilize this egg and other conditions are also favorable, the egg implants itself on the uterine wall and pregnancy occurs.
If fertilization doesn’t occur and the woman doesn’t get pregnant, she starts menstruating.
Only a 24-hour window exists for the egg to get fertilized, but the sperm can stay alive for 3 to 5 days inside a woman’s body.
Emergency contraceptive pills or morning after pills work by either preventing ovulation or fertilization or by preventing attachment of the fertilized egg to the wall of the uterus based on the stage of women’s menstrual cycle.
The morning after pills that contain levonorgestrel, either delay or completely prevent the release of an egg. You need to take 2 pills containing 0.75 mg of levonorgestrel under each dose. The first dose should be taken soon after unprotected sex and the second dose should be consumed at a gap of 12 hours of the first dose.
The way in which levonorgestrel works is still unclear, but it is believed that it disrupts the meeting of the egg and the sperm in the fallopian tubes. This is caused due to the unnatural increase in the levels of hormone in the body. Levonorgestrel will be less effective if the ovulation has already occurred.
Mifepristone is another ingredient also used in some types of morning after pills. It is a steroid that causes abortion in early pregnancy.
