Abstract: Background：In recent years, with the rapid development of fetal medicine in China, intrauterine operations have been widely carried out across the country. At present, the evaluation of fetal medical intervention effects is mostly based on single center with a small sample data and the limitation to the perinatal outcome. There is a lack of multicenter, large sample studies on the shortterm and longterm prognosis of fetuses after birth. Objective：To describe the current status and prognosis of very preterm infants who received intrauterine operations and/or invasive prenatal interventions in 57 NICUs of the Chinese Neonatal Network (CHNN) in 2019. Design：Cohort study. Methods：This study took CHNN very preterm infants as the cohort population. Infants who received intrauterine operations and/or invasive prenatal interventions (including fetoscopic laser photocoagulation, selective fetal reduction, fetal transfusion, shunt placement, amnioreduction, and amniotic fluid and/or chorionic villus sampling) were matched to infants without prenatal interventions using propensity scores by the ratio of 1 to 4. Mortality (in NICU, 28 days after birth and 7 days after birth) and major morbidities (severe brain injury, retinopathy ≥ stage Ⅲ, bronchopulmonary dysplasia, necrotizing enterocolitis ≥ stage Ⅱ and sepsis) were compared between the two groups. Main outcome measures：Mortality. Results：A total of 9 520 very preterm infants were admitted to 57 NICUs in CHNN in 2019. Among them, 187 (2.1%) infants received intrauterine operations and/or invasive prenatal interventions, including 69 selective fetal reduction, 66 amniotic fluid and/or chorionic villus sampling, 42 amnioreduction, 20 fetoscopic laser photocoagulation, 10 fetal transfusion, and 2 shunt placement. The NICU allcause mortality of very preterm infants undergoing intrauterine operations and/or invasive prenatal interventions was 15.5% (29/187), with 22 deaths occurring within 7 days after birth. The most common morbidities among infants with prenatal interventions were bronchopulmonary dysplasia (41.7%), sepsis (11.8%), and severe brain injury (9.4%). The NICU mortality and rates of major morbidities were not significantly different from infants with prenatal interventions and the matched control group. While the mortality within 7 days (RR=1.69, 95%CI:1.06~2.71) and the incidence of early onset sepsis (RR=3.20, 95%CI:1.28~7.99) were significantly higher in infants who received intrauterine operations and/or invasive prenatal interventions. Conclusion：Overall, 2.1% of very preterm infants admitted to Chinese NICUs received intrauterine operations and/or invasive prenatal interventions. Intrauterine operations and/or invasive prenatal interventions did not significantly increase mortality and morbidities among very preterm infants.

Key words: Intrauterine operations, Invasive prenatal interventions, Very preterm infants