How does a patch stop pregnancy?

A contraceptive patch prevents pregnancy primarily by releasing hormones, such as estrogen and progestin, into the bloodstream. These hormones inhibit ovulation, meaning they stop the ovaries from releasing eggs. Additionally, the patch thickens cervical mucus, which makes it harder for sperm to enter the uterus, and it thins the uterine lining, reducing the likelihood of implantation should fertilization occur.