The Impact of Spontaneous versus Indicated Preterm Birth on Neonatal Outcomes among Extremely Premature Neonates

Abstract

Objective This study aimed to investigate whether neonatal morbidity differs in spontaneous compared with indicated preterm births in extremely premature neonates.

Study Design This is a retrospective cohort study including births ≤28 weeks at a single institution from 2011 to 2020. Births were categorized as either medically indicated or spontaneous preterm deliveries. The primary outcome was inhospital mortality and serious morbidity in survivors. t-tests, Fisher's exact tests, chi-square tests, and logistic regression models were utilized as appropriate. p < 0.05 was significant.

Results Two hundred and twenty-seven births were included, with two-thirds representing spontaneous births (65.6%, 149/227) and one-third categorized as medically indicated births (34.4%, 78/227). Inhospital mortality was more common in the spontaneous preterm birth group (p = 0.04), while inhospital morbidity did not significantly vary between the medically indicated and spontaneous birth groups (p = 0.32). There was no difference in inhospital morbidity or mortality by maternal race. In multivariate models of inhospital morbidity and mortality, gestational age was the only significant predictor of adverse outcomes.

Conclusion Despite inhospital mortality being more common in spontaneous preterm births, inhospital mortality and significant morbidity are best accounted for by gestational age alone.

Key Points

• Inhospital death is more common in spontaneous preterm births.

• Perinatal outcomes do not differ on the basis of racial/ethnic group.

• Gestational age is the best predictor of inhospital morbidity and mortality.

Keywords

preterm birth - neonatal morbidity - extreme prematurity - spontaneous preterm delivery - indicated preterm delivery

Publication History

Received: 11 April 2022

Accepted: 26 September 2023

Accepted Manuscript online:
29 September 2023

Article published online:
03 November 2023

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