Ovulation and birth after administration of progesterone trigger-two case reports.

Purpose: To determine whether using progesterone as a trigger of a gonadotropin surge will induce ovulation and a competent corpus luteum.

Methods: Patients were administered 5 or 10 mg of progesterone intramuscularly when the leading follicle reached preovulatory size.

Results: We demonstrate that progesterone injections result in classical ultrasonographic hallmarks of ovulation about 48 h later and the formation of a corpus luteum competent to support pregnancy.

Conclusion: Our results support further exploration of using progesterone to trigger a gonadotropin surge in assisted human reproduction.