Taken regularly it stops ovulation the release of a woman's egg each month.

Acts in a similar way to the mini-pill and also stops ovulation.

In some cases, mini pills stop ovulation (the release of an egg).

Your doctor may suggest that you take birth control pills, which stop ovulation.

High androgen in a woman causes male-type hair and acne problems and can stop ovulation.

Birth control pills, which stop ovulation, are often helpful.

The drug stops ovulation and may prevent a fertilized egg from implanting in the uterus.

This stops monthly ovulation and the growing, shedding, and bleeding that makes endometriosis painful.

This stops ovulation and lowers estrogen, shrinking endometriosis growths and reducing pain for most women.

So, in fact, they primarily work by stopping ovulation from occurring each cycle.