what hormones are in plan b
Each pill contains levonorgestrel, a synthetic version of the hormone progestin. Levonorgestrel has been used in birth control pills for over 35 years. Plan B One-Step contains a higher dose of levonorgestrel than that in regular birth control pills.
Levonorgestrel is a manufactured hormone used in a number of birth control methods. In pill form, sold under the brand name Plan B among others, it is useful within 120 hours as emergency birth control. It becomes less effective the longer after sex and only works before pregnancy has occurred. It is also combined with an estrogen to make combined oral birth control pill.