Works in three ways, 1- by inhibiting ovulation
, 2-by creating a very thin lining(endometrium
), making it difficult for a fertilized egg to implant
in the uterus
, 3-creates a hostile cervical mucus that doesn't allow the sperms to undergo capacitation and swim freely upstream. Also decreases to motility of the tubes making it difficult for sperm
and egg to get together.