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Review
. 2024 Jun 1;67(2):433-457.
doi: 10.1097/GRF.0000000000000867. Epub 2024 Apr 5.

Vaginal Progesterone to Prevent Spontaneous Preterm Birth in Women With a Sonographic Short Cervix: The Story of the PREGNANT Trial

Roberto Romero  1   2   3 , Arun Meyyazhagan  1   4   5 , Sonia S Hassan  4   6   7 , George W Creasy  8 , Agustin Conde-Agudelo  9
Affiliations
Review

Vaginal Progesterone to Prevent Spontaneous Preterm Birth in Women With a Sonographic Short Cervix: The Story of the PREGNANT Trial

Roberto Romero et al. Clin Obstet Gynecol. .

Abstract

The PREGNANT trial was a randomized, placebo-controlled, multicenter trial designed to determine the efficacy and safety of vaginal progesterone (VP) to reduce the risk of birth < 33 weeks and of neonatal complications in women with a sonographic short cervix (10 to 20 mm) in the mid-trimester (19 to 23 6/7 wk). Patients allocated to receive VP had a 45% lower rate of preterm birth (8.9% vs 16.1%; relative risk = 0.55; 95% CI: 0.33-0.92). Neonates born to mothers allocated to VP had a 60% reduction in the rate of respiratory distress syndrome. This article reviews the background, design, execution, interpretation, and impact of the PREGNANT Trial.

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Figures

FIGURE 1
FIGURE 1
Participant flow diagram (reused with permission).
FIGURE 2
FIGURE 2
Survival analysis of intent-to-treat analysis set showing the proportion of patients remaining undelivered according to treatment allocation: vaginal progesterone (VP; ——) versus placebo (- - - - ). A, Entire population (patients with and without a prior history of preterm delivery; VP, n = 235; placebo, n = 223). B, Patients without a prior history of preterm delivery (VP, n = 197; placebo, n = 189). C, Patients with a prior history of preterm delivery (VP, n = 38; placebo, n = 34). P >0.05 for all comparisons (reused with permission).
FIGURE 3
FIGURE 3
The rate of preterm delivery at different gestational ages: PREGNANT trial.
See this image and copyright information in PMC

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