Abortus imminens adalah perdarahan yang terjadi sebelum usia kehamilan 20 minggu, tanpa keluarnya janin. Selama kehamilan, progesteron berperan dalam proses implantasi janin ke dalam rahim. Beberapa penelitian menunjukkan bahwa progesteron bermanfaat dalam penanganan abortus imminens, baik dalam bentuk oral maupun supositoria. Sediaan oral terbukti lebih efektif dibandingkan progesteron vaginal. Threatened miscarriage or imminent abortion is vaginal bleeding that happened before a 20-week gestation without fetus expulsion. During pregnancy, progesterone plays a role in the process of implanting the fetus into the uterus. Several studies have shown that oral and suppository progesterone are beneficial for imminent abortion treatment, both in oral and suppository form. Oral preparations have proved to be more effective than vaginal progesterone.