Mechanism of action of the morning-after pill

The morning-after pill should be taken shortly after sexual intercourse, since it is most effective within 12 hours. However, it can be taken up to 72 hours after intercourse to avoid unwanted pregnancy.

Depending on the time of the menstrual cycle in which it is taken, its mechanism of action may be different. First of all, postday inhibits ovulation if it has not yet taken place. It also has an effect on cervical mucus to prevent the passage of sperm. Finally, there is a modification of the endometrium to prevent the implantation of the embryo if fertilization has already taken place.