Effects of parity on preterm delivery in twin gestations conceived with in vitro fertilization

Michael S Awadalla; Wael H Salem; Jacqueline R Ho; Victoria K Cortessis; Ali Ahmady; Richard J Paulson

doi:10.1016/j.xfre.2023.01.005

Effects of parity on preterm delivery in twin gestations conceived with in vitro fertilization

F S Rep. 2023 Jan 21;4(1):49-54. doi: 10.1016/j.xfre.2023.01.005. eCollection 2023 Mar.

Authors

Michael S Awadalla¹, Wael H Salem¹, Jacqueline R Ho¹, Victoria K Cortessis^{1

2}, Ali Ahmady¹, Richard J Paulson¹

Affiliations

¹ Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, Keck School of Medicine, University of Southern California, Los Angeles, California.
² Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, California.

Abstract

Objective: To determine the relationship between prior obstetrical history and gestational age at delivery in a twin pregnancy.

Design: Retrospective cohort study using the United States Society for Assisted Reproductive Technology Clinic Outcomes Reporting System database.

Setting: Clinic-based data.

Patients: Patients undergoing in vitro fertilization (IVF) in the United States with live delivery of twins.

Interventions: None.

Main outcome measures: The main outcome measures are median gestational age at delivery and rate of preterm delivery (before 37 weeks).

Results: The median gestational age at delivery of IVF-conceived twins was 36.3 (interquartile rate 34.4, 37.6) weeks for nulliparous women, 35.9 (34.0, 37.1) weeks for parous women with a prior preterm birth, and 36.7 (35.1, 37.7) weeks for parous women without a prior preterm birth. The rate of preterm delivery was 61% for nulliparous women, 70% for parous women with a prior preterm birth, and 55% for parous women without a prior preterm birth.

Conclusions: Parous women without a history of preterm delivery had lower rates of preterm delivery in a subsequent twin pregnancy than nulliparous women. Nulliparous women had lower rates of preterm delivery compared with parous women with a history of preterm delivery.

Keywords: In vitro fertilization; parity; preterm delivery; twin gestation.