Progestagens for preventing preterm birth

Keywords:

progestagens, Progesterone, 17 α OH Progesterone, 17 α OH Progesterone Caproate, preterm labour, preterm birth

F. Facchinetti, V. Vaccaro, E. Annessi, G. Dante
Mother-Infant Department, Unit of Obstetrics, University of Modena and Reggio Emilia, Italy

Correspondence at: fabio.facchinetti@unimore.it

Abstract

The term “progestagens” covers a group of molecules including both the natural female sex hormones Progesterone and 17-hydroxy Progesterone as well as several synthetic forms, all displaying the ability to bind Progesterone receptors. Several studies have used Progesterone and related steroids in an attempt to prevent spontaneous preterm birth (PTB).
The present paper aims to provide a comprehensive review of the literature on the effects of progestagens effects in preventing spontaneous PTB. We consider only the information derived from randomized controlled trials (RCTs). Results are reported in 4 sections according to the clinical risk factor: 1- history of preterm delivery, 2- short cervix, either symptomatic or asymptomatic, 3- multiple pregnancies, 4- threatened preterm labour.

For the clinicians, the back home message is that a) 17 OH Progesterone caproate (17OHPc) is able to prevent PTB in women at risk because of their obstetric history, and b) vaginal Progesterone prevents PTB in women with an asymptomatic short cervix. The conclusion that progestagens are useless in multiple gestations has recently been challenged by an individual participant data (IPD) meta-analysis. No firm indications on the use of progestagens for PTB prophylaxis in women presenting with other risk factors such as symptomatic short cervix or threatened preterm labour could be found with the available data.