Numerous studies have shown that outborn preterm infants born at 23+0-28+6 weeks' gestation in maternity units without on-site neonatal intensive care unit (NICU) have higher rates of mortality and severe disability compared with inborn infants (delivered in maternity units with on-site neonatal intensive care). These differences are partly explained by variations in maternal characteristics, as well as in resuscitation and transport conditions. To date, no study has evaluated the impact of the presence of a neonatal transport team (NNT) beyond short-term transport-related complications.
The primary objective is to assess the effect of the antenatal NNT positioning, compared with postnatal NNT positioning, on survival without major neurodevelopmental sequelae at two years of corrected age (CA) in outborn preterm infants born at 23+0-28+6 weeks' gestation.
Secondary objectives will evaluate the effects on morbidity and mortality and neonatal health, medical interventions and the infant's stability during transport, healthcare utilization, as well as parents' experiences, mental health, and quality of life throughout follow-up. Cost-effectiveness and budget impact will also be examined, along with social and geographic inequalities in morbidity and mortality at two years. Barriers to and facilitators of organizing pediatric transport for outborn preterm infants will be identified in collaboration with neonatal transport teams.
The population included in the OutbornTRANSFER study are extremely preterm newborns born in mainland France in a maternity unit without on-site neonatal intensive care, and managed by one of the 32 specialized neonatal transport teams.
A national, multicenter, observational, longitudinal cohort will be established over a two-year period, including all outborn births between 23+0-28+6 weeks' gestation for which a NNT is deployed and who are alive at the moment of arrival of the NNT. Preterm outborn infants and their families will be followed until the child reaches two years of corrected age.
An economic evaluation will also be conducted, as well as a mixed-method study among medical professionals from participating NNT.
If the infant survives and is transported to a neonatal intensive care unit, the NNT investigator will inform the parents about the study and invite them to participate. If the investigator is unable to meet the parents, an information leaflet and a flyer (including a unique identification number and a QR code) will be placed in the child's health record booklet, enabling parents to access a study-specific electronic data collection application and to provide their non-opposition online.
Data on birth, initial care, transport, and timing of NNT positioning will be collected using the NNT data transportation sheet dedicated to the study, completed by the NNT study investigator.
The NNT study investigator will obtain hospitalization discharge reports, which include relevant medical history, pregnancy course, birth details, and the infant's hospital stay, with particular focus on severe conditions relevant to the cohort's outcome measures.
One month after hospital discharge, a research assistant will contact both parents to re-explain the telephone follow-up procedures, including the collection of data on parental experiences during hospitalization, parental mental health, and health-related quality of life since discharge. Subsequent telephone assessments will be conducted at 6, 12, 18, and 24 months corrected age.
A collaboration will be established with the Vulnerable Children Network (Réseau de Suivi des Enfants Vulnérables - RSEV), which organizes and performs auditory, ophthalmological, psychological, and physical assessments of premature infants, including the Ages and stages questionnaire (ASQ). One month prior to the infant's 24-month corrected age visit, the research assistant will contact the parents to present the ASQ-3 and encourage completion during the RSEV pediatric visit or directly via the study web app if they do not participate in the network follow-up. The research assistant will then collect the reports from the RSEV pediatrician for the 24-month visit.
The investigators will link the cohort data with data from national health data system (SNDS - Système National des Données de Santé) to evaluate healthcare consumptions by the mother (and subsequently the premature infant) during pregnancy and up to 24 months corrected age of the infant.
