NCIt definition : A synthetic form of the naturally occurring female sex hormone progesterone. Etonogestrel
binds to the cytoplasmic progesterone receptors in the reproductive system and subsequently
activates progesterone receptor mediated gene expression. As a result of the negative
feedback mechanism, luteinizing hormone (LH) release is inhibited, which leads to
an inhibition of ovulation and an alteration in the cervical mucus and endometrium.;