Effects of intravaginal oestrogen treatment upon the vaginal absorption of conjugated equine oestrogens.
Conjugated equine oestrogens (0.625 mg) were administered daily and intravaginally to 7 postmenopausal women (aged 70-93 yr) for 14 days. Blood samples were taken at days 1 and 14 immediately before and 2, 4 and 6 h after oestrogen application and at days 4, 6, 8, 11 and 13, 4 h after application. Serum samples were analyzed with respect to total oestrone (E1), unconjugated 17 beta-oestradiol (E2), FSH and LH. Serum total E1 and E2 increased rapidly at day 1 to luteal and follicular phase levels respectively. After that total E1 levels decreased to a plateau corresponding to follicular phase values and remained at that level throughout the treatment period. Serum E2 remained at the follicular phase level during the entire period of treatment. No increase in serum oestrogens could be detected after oestrogen application at day 14. Serum gonadotrophins were already suppressed at day 4 and further decreased to premenopausal values during the latter half of the treatment period. It is speculated that the effects of oestrogens upon a post-menopausal vaginal mucosa involves a diminished resorption of conjugated oestrogens. This effect is, however, not sufficient to avoid systemic effects at the dosage used.
D000042:Absorption; D000368:Aged; D004958:Estradiol / Q000378:metabolism; D004966:Estrogens, Conjugated (USP) / Q000008:administration & dosage / Q000378:metabolism* / Q000494:pharmacology; D004970:Estrone / Q000378:metabolism; D005260:Female; D006801:Humans; D014621:Vagina / Q000187:drug effects / Q000378:metabolism*
D004966:Estrogens, Conjugated (USP); D004970:Estrone; D004958:Estradiol