Elsa Lorthe, Gilles Kayem, Centre de Recherche Épidémiologie et Statistique Sorbonne Paris Cité (CRESS (U1153 / UMR_A_1125 / UMR_S_1153)), Conservatoire National des Arts et Métiers [CNAM] (CNAM), HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-Université Sorbonne Paris Cité (USPC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Paris Cité (UPCité)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Geneva University Hospitals and Geneva University, Service de Gynécologie-Obstétrique [CHU Trousseau], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Trousseau [APHP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU), OCOPROM Study Group and the GROG (Groupe de Recherche en Obstétrique et Gynécologie): Gilles Kayem, Elsa Lorthe, Pierre-Yves Ancel, Hendy Abdoul, Nelly Briand, Blandine Lehmann, Clémence Cabanne, Stéphane Marret, Laurence Foix l'Hélias, François Goffinet, Thomas Schmitz, Caroline Charlier, Fanny Autret, Elie Azria, Jadot Balitalike, Kareen Billiemaz, Caroline Bohec, Pascal Bolot, Marie Bornes, Hanane Bouchghoul, Malek Bourennane, Florence Bretelle, Lionel Carbillon, Christine Castel, Céline Chauleur, Romain Corroenne, Karen Coste, Valérie Datin-Dorrière, Raoul Desbriere, Luc Desfrere, Michel Dreyfus, Marc Dommergues, Xavier Durrmeyer, Géraldine Favrais, Cyril Flamant, Denis Gallot, Julie Gries, Bassam Haddad, Laure Julé, Cécile Laffaille, Jacques Lepercq, Emmanuelle Letamendia, Fanny de Marcillac, Caroline Miler, Olivier Morel, Karine Norbert, Franck Perrotin, Christophe Poncelet, Laurent Renesme, Claire Roumegoux, Patrick Rozenberg, Mireille Ruiz, Loïc Sentilhes, Jeanne Sibiude, Damien Subtil, Nadia Tillouche, Héloïse Torchin, Barthélémy Tosello, Eric Verspyck, Alexandre Vivanti, Norbert Winer, Malbec, Odile, and Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Université Sorbonne Paris Cité (USPC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Paris (UP)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
Background Preterm prelabor rupture of membranes (PPROM) before 34 weeks of gestation complicates 1% of pregnancies and accounts for one-third of preterm births. International guidelines recommend expectant management, along with antenatal steroids before 34 weeks and antibiotics. Up-to-date evidence about the risks and benefits of administering tocolysis after PPROM, however, is lacking. In theory, reducing uterine contractility could delay delivery and reduce the risks of prematurity and its adverse short- and long-term consequences, but it might also prolong fetal exposure to inflammation, infection, and acute obstetric complications, potentially associated with neonatal death or long-term sequelae. The primary objective of this study is to assess whether short-term (48 h) tocolysis reduces perinatal mortality/morbidity in PPROM at 22 to 33 completed weeks of gestation. Methods A randomized, double-blind, placebo-controlled, superiority trial will be performed in 29 French maternity units. Women with PPROM between 220/7 and 336/7 weeks of gestation, a singleton pregnancy, and no condition contraindicating expectant management will be randomized to receive a 48-hour oral treatment by either nifedipine or placebo (1:1 ratio). The primary outcome will be the occurrence of perinatal mortality/morbidity, a composite outcome including fetal death, neonatal death, or severe neonatal morbidity before discharge. If we assume an alpha-risk of 0.05 and beta-risk of 0.20 (i.e., a statistical power of 80%), 702 women (351 per arm) are required to show a reduction of the primary endpoint from 35% (placebo group) to 25% (nifedipine group). We plan to increase the required number of subjects by 20%, to replace any patients who leave the study early. The total number of subjects required is thus 850. Data will be analyzed by the intention-to-treat principle. Discussion This trial will inform practices and policies worldwide. Optimized prenatal management to improve the prognosis of infants born preterm could benefit about 50,000 women in the European Union and 40,000 in the United States each year. Trial registration ClinicalTrials.gov identifier: NCT03976063 (registration date June 5, 2019).