Clinical Report: Delivery Patterns After In Utero Transfer for Extremely Preterm Birth

Overview

This retrospective cohort study at St George’s Hospital examined delivery patterns after in utero transfer (IUT) for threatened extremely preterm birth between January 2021 and December 2025. The supplied article text describes the study population, setting, eligibility criteria, and planned measures, but does not provide cohort results or numerical outcomes.

Background

London perinatal services are organised through an Operational Delivery Network linking hospitals with different levels of neonatal care. The article states that IUT enables birth at a tertiary centre with neonatal intensive care and is associated with better neonatal outcomes than early postnatal transfer for extremely preterm infants. Maternal instability, imminent birth, and logistical barriers can prevent IUT, while postnatal transfer has been associated in cited evidence with higher mortality and severe brain injury. The study was designed to describe transfer-to-delivery intervals and maternal length of stay, areas the authors identify as less well characterised.

Data Highlights

The supplied study text reports no cohort size, delivery intervals, length-of-stay results, or other numerical findings. It specifies a retrospective cohort at St George’s Hospital covering accepted IUT episodes from January 2021 through December 2025.

Key Findings

• The study included women accepted for IUT for threatened preterm birth at 22+0–27+6 weeks, or at 28–29 weeks when a multiple pregnancy was present or expected birth weight was below 800 g.
• Transfers solely for fetal anomalies incompatible with survival, non-preterm indications, and cases of intrauterine death before transfer were excluded; repeat transfers were counted as separate episodes.
• Data were drawn from BadgerNet, electronic maternity records, and delivery suite databases.
• Recorded measures included gestational age at transfer, referral indication and network, transfer-to-delivery interval, maternal length of stay, and discharge outcomes.
• The article’s background reports that IUT is associated with better neonatal outcomes than postnatal transfer and cites evidence linking postnatal transfer among extremely preterm infants with higher mortality and severe brain injury.
• The supplied text does not include the study’s results, so delivery patterns and maternal length-of-stay outcomes cannot be summarised.

Clinical Implications

The article frames transfer-to-delivery timing and maternal length of stay as information relevant to referral thresholds, triage, family counselling, and inter-hospital practice. No study results are provided in the supplied text to support specific changes to clinical practice.

Conclusion

The supplied material establishes the rationale and methods for a London tertiary-centre cohort study of delivery after IUT for threatened extremely preterm birth. Its principal outcome findings are not available in the provided text.

Related Resources & Content

1. British Association of Perinatal Medicine, 2026 — Perinatal Management of Extreme Preterm Birth Before 27 Weeks of Gestation
2. Observational cohort study with propensity score matching — Association of early postnatal transfer and birth outside a tertiary hospital with mortality and severe brain injury in extremely preterm infants
3. The Journal of Clinical Endocrinology & Metabolism — Outcomes of Perinatal and Maternal Health Following Transfer of Blastocysts from Nonpronuclear and Monopronuclear Embryos
4. BMC Pregnancy and Childbirth — Intrapartum cardiotocographic patterns and perinatal outcomes in extremely preterm births: an exploratory retrospective cohort study
5. Frontiers in Pediatrics — Neonatal Outcomes Following Out-of-Hospital Births: A Retrospective Cohort Analysis from a Level IV NICU and Examination of Regulatory Policies
6. BMJ Paediatrics Open — Optimising transfusion practices in preterm neonates using gestational age and birth weight-based prediction model: a retrospective cohort study from India
7. Perinatal Management of Extreme Preterm Birth Before 27 Weeks of Gestation (2026)
8. Association of early postnatal transfer and birth outside a tertiary hospital with mortality and severe brain injury in extremely preterm infants
9. Neonatal Interfacility Transport to Tertiary and Quaternary Centres: Clinical Outcomes and System-Level Determinants—A Systematic Review - PMC