The impact of Assisted Reproductive Technology on the neonatal prognosis of newborns < 29 weeks gestational age: a retrospective case-control study

OBJECTIVE: To evaluate the neonatal prognosis of preterm infants born before 29 weeks of gestation based on their mode of conception (Medically Assisted Reproduction vs spontaneous pregnancy). DESIGN: A retrospective case-control study was conducted in the neonatal intensive care unit of the Hôpital de la Conception in Marseille. SUBJETCS: All preterm newborns under 29 weeks of gestation hospitalized between 2014 and 2020 were included. Newborns conceived through Medically Assisted Reproduction were compared to a control group of newborns from spontaneous pregnancies, matched at a ratio of 1 case to 3 controls. EXPOSURE: Medically Assisted Reproduction MAIN OUTCOME MESURES: The primary outcome was a composite criterion including the number of deaths, bronchopulmonary dysplasia at 36 weeks of gestation, severe intraventricular hemorrhage (grade 3 or higher), severe retinopathy of prematurity (grade 3), and/or necrotizing enterocolitis (grade 2 or higher). Secondary outcomes included Apgar score, cesarean section rate, and average age at discharge from neonatal intensive care. RESULTS: Among the 616 hospitalized newborns, 18.8% were conceived through Medically Assisted Reproduction (n=112). A total of 448 patients were included, with 112 cases and 336 controls. Among the cases, 21 were conceived via intrauterine insemination, 14 through ovulation stimulation with clomiphene, 54 through In Vitro Fertilization, and 23 through IntraCytoplasmic Sperm Injection. Multiple pregnancies were more common in the Medically Assisted Reproduction group (61.6%) compared to spontaneous conception (30.6%). No significant difference was observed in the neonatal prognosis between newborns conceived via Medically Assisted Reproduction and those from spontaneous pregnancies (74.1% vs 77.1%, p=0.52). The cesarean section rate was significantly higher among mothers who underwent Medically Assisted Reproduction (83% vs 59.2%, p<0.05). CONCLUSION: This study suggests that newborns under 29 weeks of gestation conceived through Medically Assisted Reproduction have a neonatal prognosis comparable to those from spontaneous pregnancies, although cesarean section rates are higher among mothers who used Medically Assisted Reproduction.