INTRODUCTION
It is assumed that the cause of spontaneous miscarriage in many cases is insufficient secretion of progesterone, but numerous studies on the effectiveness of various forms of progestogens for the prevention of threatened miscarriage and recurrent miscarriage (RNP) are contradictory.
MAIN RESULTS AND PROVISIONS
Studies show that dydrogesterone has clear benefits for preventing threatened miscarriage (odds of live birth from 1.03 to 1.77) compared with placebo or other forms of progestogen). The effectiveness of dydrogesterone in RPL for its prevention during the current pregnancy is also beyond doubt (from 1.54 to 4.26). Vaginal progesterone is appropriate in pregnant women with RPL and symptoms of a threatened miscarriage (from 1.09 to 1.28), in other cases, outcomes do not depend on its use, including in preconception preparation. In ART programs, individualization of doses and routes of administration of progesterone may lead to a reduction in miscarriage and improved outcomes, but which treatment strategy is best is still under investigation. Dydrogesterone is recommended to be administered as early as possible — when diagnosing pregnancy or during the luteal phase, in stimulated cycles. Studies confirm the safety in relation to the action of dydrogesterone and progesterone formulations on the body of a pregnant woman and a child.
CONCLUSION
Dydrogesterone in the prevention of threatened miscarriage before 20 weeks of gestation is more effective than vaginal PG. Treatment of women with recurrent miscarriages with dydrogesterone is 2 to 4 times more effective than other strategies. The available data are insufficient to recommend the use of vaginal and rectal and injectable PGs for the treatment of threatened or recurrent miscarriage. The effectiveness of luteal phase support in ART programs, doses and routes of administration of PG continue to be studied.