The Role of Progestogens in Menopausal Hormone Therapy.

Progestogens are steroid compounds that have the ability to induce secretory transformation in the endometrium and are utilized in menopausal hormone therapy to prevent endometrial hyperplasia and endometrial cancer. Progestogens can be derived from 21-carbon or 19-carbon steroid cytoskeletons and thus have different properties and metabolic effects beyond the progestational effects on the endometrium. This limited review will focus on the available progestogens utilized in combination hormone therapy including progesterone, medroxyprogesterone acetate, norethindrone, norethindrone acetate, levonorgestrel, and drospirenone. The impact of progestogens on a variety of target tissues including the endometrium, breast, cardiovascular system, brain, and bone, will be reviewed. Last, the current clinical regimens that can be utilized by clinicians will be discussed.