A doctor administers an injection once every three months. This birth control method suppresses ovulation, thickens the cervical mucus and thins the lining of the uterus.
Over 99 percent effective.
Hormonal Intrauterine Device (IUD)
Brand name: Mirena
How it works
A doctor implants the Mirena IUD directly into a woman’s uterus and it becomes effective immediately upon insertion. The device can be left in the body for up to five years before a doctor removes it. It works by thinning the lining of the uterus, thickening cervical mucus and inhibiting sperm movement.