title: Mid-gestation pregnancy termination by the progesterone antagonist aglepristone in queens.
abstract: The efficacy of aglepristone, a progesterone receptor antagonist, to induce abortion on days 25 and 26 after first mating was investigated in queens. The cats were divided into two groups: aglepristone (10 mg/kg, subcutaneously) was injected twice, 24 h apart, on days 25 and 26 after first mating, into group I queens (n = 23). Group II queens (n = 6) were not treated and served as controls. Termination of pregnancy and expulsion of the fetuses were successful in 20 (87%) queens in group I. The mean interval between the first administration of aglepristone and the beginning of vaginal discharge was 5+/-1 days (range 4-7 days) and the mean duration of abortion, defined as time span from first occurrence of vaginal discharge to expulsion of all fetuses observed by ultrasonography was 1 day in nine cats, 2 days in five cats and in five cats, less than 1 day. Treatment failed in three queens. In one queen treatment resulted in birth (66 days after mating) of two vital kittens. In another case, three macerated fetuses were found intrauterine without vaginal discharge. In one cat, two fetuses were expulsed and two remained intrauterine and were born 66 days after last mating. All group II queens gave birth to vital kittens after a normal pregnancy length. The mean serum P4 concentrations were similar in treated and control animals. The results indicate that aglepristone treatment at day 25 of pregnancy could induce abortion in 87% of the treated queens. Itching at the site of injection right after injection was the only side effect noticed and only in one queen.
authors.affiliation: Department of Obstetrics, Gynaecology and Andrology, Faculty of Veterinary Medicine, Thracian University Stara Zagora, Malka Verea, B-6000 Stara Zagora, Bulgaria. plana@abv.bg
authors.forename: Plamen
authors.initials: P
authors.lastname: Georgiev
authors.forename: Axel
authors.initials: A
authors.lastname: Wehrend
mesh_terms: D000028:Abortion, Induced / Q000379:methods / Q000662:veterinary*; D000034:Abortion, Veterinary; D000818:Animals; D002415:Cats; D004963:Estrenes / Q000008:administration & dosage*; D005260:Female; D005865:Gestational Age; D011247:Pregnancy; D011374:Progesterone / Q000037:antagonists & inhibitors* / Q000097:blood
chemical_list: D004963:Estrenes; C419063:aglepristone; D011374:Progesterone