15.06.1 Emergency contraception

The ‘morning-after pill’ contains a high dose of levonorgestrel, which is progesterone-like (progestogen) drug.  Levonorgestrel inhibits the production of luteinizing hormone by the pituitary gland, which in turn prevents ovulation and fertilisation. The earlier oral levonorgestrel is taken the better, preferably within 3 days, but it can be effective up to 5 days after sexual intercourse.