Abstract: | Seventeen patients were studied for the first 72 hours of the luteal phase after spontaneous ovulation or follicle aspiration. Nine patients (group I) underwent follicle aspiration after clomiphene citrate (CC) administration, three women were studied after CC for ovulation induction (group II), and five spontaneous ovulating subjects served as controls (group III). Serum progesterone (P) concentrations were significantly elevated in stimulated cycles with or without follicle aspiration, compared with subjects. Moreover, when aspirated subjects were compared with nonaspirated stimulated subjects, a significant difference in P concentration was identified. It can be concluded that with follicle aspiration, P decreases can be observed, but with multiple follicle development, inadequate P levels are not seen in these stimulated subjects. On the contrary, with such elevated P levels, endometrial advancement may play a role in poor implantation success with human in vitro fertilization procedures. |