Birth control contains two tpyes of steriods that copy the effects of natural hormones, estrogen and progesterone. Their effectiveness relies on three mechanisms:
1.Preventing ovulation from occurring.
2.Changing the cervical mucus to prevent or delay the sperm from entering the uterus.
3.Preventing the implantation of a newly conceived baby onto the lining of the mother’s womb.
Birth control is relatively safe considering it is 99.5% effective. Studies show it only fails to prevent pregnancy in 1 out of every 100 women ( if taken correctly). However hormonal birth control does not protect against STDs.