Question:

Dear expert,

I wonder why every emergency contraceptive pill contains only Levonorgestrel but nothing else. I have been told that Levonorgestrel is one of the progesterone hormone.

Why don`t emergency contraceptive pill contain other progesterone hormones? Because it is not effective?

Answer:

Thank you for contacting Net Wellness. Emergency contraception is only effective prior to pregnancy not to terminate an existing pregnancy. Emergency contraception can prevent pregnancy during the five or more days between intercourse and implantation of a fertilized egg, but it is ineffective after implantation.

 

Methods of emergency contraception include administration of progestin only combination of estrogen/progestin oral contraceptives, synthetic estrogens and conjugated estrogens, or anti-progestins and the insertion of a copper intrauterine device (IUD).

 

The levonorgestrel-only regimen is more effective and is associated with less nausea and vomiting, therefore, if available, it should be used in preference to the combined estrogen/progestin regimen. Plan B® (Levonorgestrel) is a synthetic and biologically active progestogen. Naturally progestogen inhibits ovulation or fertilization by alteration of tube which transports sperm into the cervix. It also thickens the cervical mucus and works to inhibits implantation by alteration of the endometrium.

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