Outcomes of Medically Indicated Preterm Births Differ by IndicationFunding Michelle J. Wang was supported by the National Center for Advancing Translational Sciences of the National Institutes of Health under Award Number TL1TR001418. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Dr. Harper is supported by K12HD001258-13, PI WW Andrews, which partially supports this work.
31 July 2017
17 November 2017
29 December 2017 (eFirst)
Objective We aim to examine whether outcomes of preterm birth (PTB) are further modified by the indication for delivery.
Study Design We performed a retrospective cohort study of all singletons delivered at 23 to 34 weeks from 2011 to 2014. Women were classified by their primary indication for delivery: maternal (preeclampsia) or fetal/obstetric (growth restriction, nonreassuring fetal status, and vaginal bleeding). The primary neonatal outcome was a composite of neonatal death, cord pH <7 or base excess < − 12, 5-minute Apgar ≤3, C-reactive protein during resuscitation, culture-proven sepsis, intraventricular hemorrhage, and necrotizing enterocolitis. Secondary outcomes included the individual components of the primary outcome. Groups were compared using Student's t-test and chi-squared tests. Logistic regression was used to adjust for confounding variables.
Results Of 528 women, 395 (74.8%) were delivered for maternal and 133 (25.2%) for fetal/obstetric indications. Compared with those delivered for a maternal indication, those with a fetal/obstetric indication for delivery had an increased risk of the composite neonatal outcome (adjusted odds ratio [AOR]: 1.9, 95% confidence interval [CI]: 1.13–3.21) and acidemia at birth (AOR: 4.2, 95% CI: 1.89–9.55).
Conclusion Preterm infants delivered for fetal/obstetric indications have worsened outcomes compared with those delivered for maternal indications. Additional research is needed to further tailor counseling specific to the indication for delivery.
This study was submitted in abstract format to the 37th annual meeting of the Society for Maternal-Fetal Medicine, Las Vegas, NV, January 23–28, 2017.
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