How Does Seasonique Work?

Seasonique™ (levonorgestrel/ethinyl estradiol) is a combined oral contraceptive, meaning it is a birth control pill that contains both an estrogen and a progestin. It is known to be extremely effective, but how does Seasonique work?
This medication works to prevent pregnancy primarily by stopping ovulation (the maturation and release of eggs from the ovaries). However, Seasonique also works by altering the cervical mucus, making it more difficult for sperm to enter the uterus, and the lining of the uterus, making it less receptive to an embryo.
There is no reason women need to have a monthly period while taking birth control pills. In fact, the "period" you experience while taking this form of contraceptive isn't really a period at all.
Because ovulation does not occur while taking Seasonique or other birth control pills, the body does not prepare for a possible pregnancy by building up the lining of the uterus. Therefore, there is no need to shed the lining, as with a regular period. Instead, the "period" that occurs due to birth control pills is actually caused by a withdrawal of the hormones in the pills, which causes bleeding.
(Click Seasonique for more information on how Seasonique works, to find out when and how to take this medication, and to learn about the warnings and precautions associated with it.)
Last reviewed by: Kristi Monson, PharmD
Pregnancy and Pain