In particular, tibolone administration, a tissue-specific compound with estrogenic, progestogenic
, and weak androgenic activities , increased muscle cross-sectional area .
The 54-isomer has strongest progestogenic
and androgenic activity, while 3[beta]-hydroxytibolone possesses the most potent oestrogenic activity via oestrogen receptor a (ER-[alpah]) .
In preovulatory follicles, small follicles are "androgenic," while larger follicles are "estrogenic" and "progestogenic
." The shift from estrogenic to progestogenic
state does not involve increase in the concentration of P and this shift is consistent with an increased steroidogenesis by granulosa cells as well as an increased LH sensitivity of granulosa cells .
Tibolone (TIB) is a synthetic steroid with estrogenic, androgenic, and progestogenic
actions that can be used as HRT.
The use of combined (Es+Pr) MHT could cause the occurrence of progestogenic
side effects, including breast tenderness, swelling due to body water retention, headaches, mood changes and depression.
Ongoing research has concentrated on lowering the doses of oestrogen and progestogen and developing progestogens that are more selective i.e., with higher progestogenic
activity and little affinity for androgen receptors.
Tibolone, which has weak androgenic, oestrogenic and progestogenic
activity and does not increase sex hormone binding globulin, can be used as an alternative to testosterone.
In addition to the foreign body effect, this IUD prevents pregnancy through progestogenic
mechanisms: It thickens cervical mucus, thins the endometrium, and reduces sperm capacitation.
An estrogenic action of diosgenin, but no progestogenic
action, has been reported following subcutaneous administration in the ovariectomised mouse (Aradhana 1992).
It has weak estrogenic, progestogenic
, and androgenic properties and has shown significant reduction in hot flashes and night sweating compared with placebo.
After ingestion it is converted to three metabolites, namely 3-alpha-and 3-beta-hydroxytibolone, which have oestrogenic effects, and delta-4-isomerase, which has progestogenic
and androgenic properties.
Non-enzyme-inducing antibiotics have no effect on the progesterone-only pill since the progestogenic
metabolites that are reabsorbed after the cleaving by gut bacteria are biologically inactive.