'Progestagens' (also spelled 'progestogens' or 'gestagens') are
hormones which produce effects similar to
progesterone, the only natural progestagen. All other progestogens are
synthetic and are often referred to as
progestins.
All progestagens have antiestrogenic (counteracting the effects of
estrogens on the body) and antigonadotropic (inhibiting the production of
sex steroids by
gonads) properties.
Progestogens differ in their potency (affinity for
progesterone receptors) and side effects. Such side effects may be
androgenic (medroxyprogesterone and most C19 progestagens),
antiandrogenic (cyproterone acetate),
estrogenic,
glucocorticoid (some C21 progestogens) or anti
mineralocorticoid (progesterone).
Uses
Birth control
★
★ Progestogens are used alone in
progestogen only pills, or with an
estrogen in
combined oral contraceptive pills, a
contraceptive patch, and a
contraceptive vaginal ring.
★
★ Medroxyprogesterone acetate (
Depo-Provera) and norethindrone enantate (Noristerat) are used by
depot injection.
★
★ Etonogestrol is released by
subcutaneous implants (
Implanon).
Norplant and
Jadelle implants release
levonorgestrel.
★
★ Levonorgestrel is released by the
intrauterine system IUS (Mirena).
Antiandrogen
Cyproterone is an
antiandrogen.
Progestogen withdrawal bleeding
In a normal
menstrual cycle, a sudden drop in progesterone levels triggers menstruation.
Norethindrone acetate (brand name Aygestin) and
medroxyprogesterone acetate (brand name Provera) may be used to artificially induce progestogen withdrawal bleeding.
External links
★
The Million Women Study
★
The Women's HOPE Study (PubMed Abstract)
★
HERS Study (JAMA Abstract)