Risk Factors of Early Mortality Within 72 Hours of Birth in 22- and 23-Week-Old Neonates

Background The survival rates of neonates is significantly influenced by gestational age, with further differences observed internationally. Survival rates for live births at 22 and 23 weeks of gestation range from 3.7–56.7% and from 20.0–79.3%, respectively. Despite advancements in neonatal care, the mortality rate in these preterm infants remains high, and the factors influencing mortality remain unclear. In this study, we conducted a comparative analysis of the risk of death within 72 h of birth in 22- and 23-week-old neonates. Methods This single-center, retrospective study analyzed 185 patients admitted to the neonatal intensive care unit between January 2006 and December 2023. Maternal information, placental pathology, out-of-hospital births, and neonatal information were compared between patients who did and did not succumb to mortality within 72 h. A logistic regression model was created with death within 72 h as the outcome variable, and fetal bradycardia, 5-min Apgar score, Umbilical arterial pH (UA pH), and tension pneumothorax as explanatory variables. Parameter estimation was performed using the likelihood method. Results In the death within 72 h after birth group, differences were observed in the mode of delivery determined by fetal bradycardia (4/15 cases, 26.7%), 1-min Apgar score (1, 95% confidence interval [CI]: 1–3 points), 5-min Apgar score (5, 95% CI: 2–6 points), UA pH (7.24, 95% CI: 7.11–7.32), and tension pneumothorax (7/15 cases, 46.7%). In the logistic regression model estimating risk factors of death within 72 h, the expected values of the regression coefficients and 95% CI were as follows: fetal bradycardia (7.89, 95% CI: 1.31–48.40), 5-min Apgar score (1.43, 95% CI: 1.04–2.03), UA pH (6.10, 95% CI: 0.09–300.93), and tension pneumothorax (8.79, 95% CI: 2.35–35.46). Conclusion Death within 72 h of birth in neonates born at 22–23 weeks gestation is associated with fetal bradycardia, low 5-min Apgar scores, and tension pneumothorax. Optimizing prenatal care, timely resuscitation, and neonatal management strategies may improve survival outcomes.