OPtimal TIming of antenatal COrticosteroid administration in pregnancies complicated by early-onset fetal growth REstriction (OPTICORE): study protocol of a multicentre, retrospective cohort study

Mette van de Meent*, Dianne G. Kleuskens, Wessel Ganzevoort, Sanne J. Gordijn, Elisabeth M.W. Kooi, Wes Onland, Bas B. van Rijn, Johannes J. Duvekot, René F. Kornelisse, Salwan Al-Nasiry, Reint K. Jellema, H. Marieke Knol, Gwendolyn T.R. Manten, Susanne M. Mulder-de Tollenaer, Jan B. Derks, Floris Groenendaal, Mireille N. Bekker, Ewoud Schuit, A. Titia Lely, Judith Kooiman

*Corresponding author for this work

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Introduction Early-onset fetal growth restriction (FGR) requires timely, often preterm, delivery to prevent fetal hypoxia causing stillbirth or neurologic impairment. Antenatal corticosteroids (CCS) administration reduces neonatal morbidity and mortality following preterm birth, most effectively when administered within 1 week preceding delivery. Optimal timing of CCS administration is challenging in early-onset FGR, as the exact onset and course of fetal hypoxia are unpredictable. International guidelines do not provide a directive on this topic. In the Netherlands, two timing strategies are commonly practiced: administration of CCS when the umbilical artery shows (A) a pulsatility index above the 95th h centile and (B) absent or reversed end-diastolic velocity (a more progressed disease state). This study aims to (1) use practice variation to compare CCS timing strategies in early-onset FGR on fetal and neonatal outcomes and (2) develop a dynamic tool to predict the time interval in days until delivery, as a novel timing strategy for antenatal CCS in early-onset FGR. Methods and analysis A multicentre, retrospective cohort study will be performed including pregnancies complicated by early-onset FGR in six tertiary hospitals in the Netherlands in the period between 2012 and 2021 (estimated sample size n=1800). Main exclusion criteria are multiple pregnancies and fetal congenital or genetic abnormalities. Routinely collected data will be extracted from medical charts. Primary outcome for the comparison of the two CCS timing strategies is a composite of perinatal, neonatal and in-hospital mortality. Secondary outcomes include the COSGROVE core outcome set for FGR. A multivariable, mixed-effects model will be used to compare timing strategies on study outcomes. Primary outcome for the dynamic prediction tool is € days until birth'. Ethics and dissemination The need for ethical approval was waived by the Ethics Committee (University Medical Center Utrecht). Results will be published in open-access, peer-reviewed journals and disseminated by presentations at scientific conferences.

Original languageEnglish
Article numbere070729
JournalBMJ Open
Issue number3
Publication statusPublished - Feb 2023

Bibliographical note

Funding Information:
This work was supported by Fonds Stichting Gezondheidszorg Spaarneland grant number 2021381 to J. Kooiman. This funding body was not involved in the development of the study design and will not be involved in conducting or reporting the results of the study.

Publisher Copyright:
© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.


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