Reviewing efficacy of progestagenes in recurrent early reproductive losses

Abstract

Recurrent miscarriages, defined as 2 or more spontaneous miscarriages in a row, are observed in 2% of all pregnancies. In the structure of all pregnancy losses, the recurrent miscarriage composes 5% to 20%. In addition, in clinical practice, there are large contradictions related to the domination of some factors and causes of reproductive losses. Although the lutein phase insufficiency (LPI) is not a confirmed reason of reproductive losses, there is a significant number of publications and scientific presentations which are focused on the use of progesterone for the reproductive losses treatment. This article presents the author’s critical view on recent studies dedicated to the use of progestagenes therapy with the objective of the prevention of early reproductive losses. Methodology, design and results of several studies of the efficacy of micronized progesterone and dydrogesterone have been analyzed. Generalized conclusions and critically important points of these studies have been defined. Among other things, special attention was dedicated to the results of the double blind, randomized, parallel-groups, placebo-controlled study by Kumar (2014), and the multicenter, randomized, placebo-controlled study PROMISE (2015). For example, in the author’s opinion, the comparison of the efficacy of dydrogesterone and micronized progesterone on the base of these studies can not be correct. As outlined in this article, progestagenes should be administered after the confirmation of the embryo viability. They should be used during the earlier stages of the pregnancy only in cases of clinically confirmed lutein phase insufficiency, as well as in patients participating in cycles and programs of assisted reproductive technologies. The issue of the correct dosing of progestagenes used in the therapy of reproductive losses is also not highlighted enough. This issue requires additional investigation, as the efficacy of the treatment will depend not only on the fact of progestagenes administration, but also on the optimal doses for each individual patient. The author expects that the accurate picture of progestagenes use for the treatment of miscarriages during the early stages of pregnancy will be reflected by the results of a randomized, double blind, placebo-controlled study (PRISM) which are expected in 2018.