Effect of PGF_2α in pseudopregnancy

Eleven nromal female volunicers received human choriouic gonadotropin (HCG) iotramuscularly to induce a pseudo-pregnam stale. Tweny-five milligrams of prostaglandin F_2α (PGF_2α) vvas adminstered intravenously at selecied times during the luleal phase to demonstrate a Iuteolytic effect. or a local effect upon the endomeurium producing early vaginal blceding Careful comparison of horinone levels and clinical details in these cycles showed that a) 1000 IU HCG daily does noi consistently prolomg that luteal phase; b) 2500 IU HCG daily does significantly prolong the lmeal phase: C) HCG administration sig-nifcranly imcrases progesterone and esiradol output in the treated luteal phase; d) prostaglandin administration at selected times during the lineai phase does not consistently decrease estradiol or progesterone output frinii the corpus lntenni or induce early vaginal bleeding; e) prostaglandin F_2α a known stimulant of uterine contrac tilily, prohialily causes vaginal bleeding by medianical means. as evideced by show of menses in patients with progesterone levels elevated above normal: F) althotgh variatious in progesterone and cstradiol output occurrd during the liours of prostaglandin infusion no consistend change was ohserved except for a compensatory rcbound in progesterone output: g) prostaglandin F_2α in the dose utilized. is not a luteolytic agent.