(1074) Progesterone therapy for prevention of recurrent preterm birth in a high risk patient population

Friday, February 10, 2023

3:30 PM – 5:00 PM

Objective: Preterm birth (PTB) is a significant global health problem and leading cause of infant mortality. The purpose of this study was to evaluate the efficacy of progesterone therapy, 17-α-hydroxyprogesterone caproate (17-OHPC) and vaginal progesterone, in the prevention of recurrent PTB in a high risk population.

Study Design: This is a retrospective cohort study examining delivery data within the LA County healthcare system. The population included 687 patients with a singleton pregnancy and a history of spontaneous PTB who delivered between 2015 and 2021. The main outcome was the rate of recurrent spontaneous PTB less than 37 weeks’ gestation. Pearson chi squared tests and independent T tests were used for categorical and continuous variables respectively.

Results: The median gestational age at start of progesterone therapy was 17 6/7 and 17 0/7 weeks’ gestation in the 17-OHPC and vaginal progesterone groups, respectively. The majority (73.1%) of the patients were Latina and 76.9% had one prior spontaneous PTB. The overall rate of recurrent PTB < 37 weeks’ gestation in the non-treatment group was 22.3%, whereas it was 29.1% in the 17-OHPC group and 14.3% in the vaginal progesterone group. The rate of recurrent PTB between 34 0/7 and 36 6/7 weeks’ gestation was 15.7% in the non-treatment group, 17.2% in the17-OHPC group, and 7.1% in the vaginal progesterone group. Between 28 0/7 and 33 6/7 weeks’ gestation, the rate of recurrent PTB in the non-treatment, 17-OHPC, and vaginal progesterone groups were 4.2%, 7.4%, and 7.1% respectively. Lastly, between 20 0/7 and 27 6/7 weeks’ gestation, the rate of recurrent PTB in the non-treatment, 17-OHPC, and vaginal progesterone groups were 2.4%, 4.4%, and 0% respectively. There was no statistically significant difference in PTB rate in any progesterone group when compared to no treatment at any of the specified gestational ages (p > 0.05 for all).

Conclusion: The incidence of recurrent PTB was reflective of population data. Progesterone therapy of any type did not significantly reduce the rate of recurrent preterm birth compared with no progesterone therapy.

Primary Author(s)

Genevieve R. Mazza, MD
OB/GYN Resident Physician
Department of Obstetrics & Gynecology, University of Southern California, Keck School of Medicine
Los Angeles, California, United States

Coauthor(s)

EK
Emi Komatsu, MD
University of Southern California / LAC + USC Medical Center
Los Angeles, California, United States

Presenting Author(s)

Madeline Ponzio, BA
University of Southern California, Keck School of Medicine
Los Angeles, California, United States

Coauthor(s)

Madeline Ponzio, BA
University of Southern California, Keck School of Medicine
Los Angeles, California, United States
CB
Claire Bai, MS
University of Southern California
Los Angeles, California, United States
VC
Victoria Cortessis, PhD
Keck School of Medicine, University of Southern California
Los Angeles, California, United States
ES
Elizabeth B. Sasso, MD
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Southern California
Los Angeles, California, United States