Explain Antifertility Drugs.

(N/A) Antifertility drugs are chemical substances used to control the population by preventing conception.
Birth control pills essentially contain a mixture of synthetic estrogen and progesterone derivatives. Both of these compounds are hormones. It is known that progesterone suppresses ovulation. Synthetic progesterone derivatives are more potent than progesterone. $Norethindrone$ is an example of a synthetic progesterone derivative most widely used as an antifertility drug.
The estrogen derivative which is used in combination with a progesterone derivative is $Ethynylestradiol$ $(Novestrol)$.