Nonspontaneous late preterm birth: etiology and outcomes

Am J Obstet Gynecol. 2011 Nov;205(5):456.e1-6. doi: 10.1016/j.ajog.2011.08.007. Epub 2011 Aug 16.

Abstract

Objective: We sought to determine the proportion of evidence-based (EB), vs non-EB (NEB) iatrogenic late preterm birth, and to compare corresponding rates of neonatal intensive care unit (NICU) admission.

Study design: We performed a retrospective cohort study. Cases were categorized as EB or NEB. NICU admission was compared between groups in both univariate and multivariate analysis.

Results: Of 2693 late preterm deliveries, 32.3% (872/2693) were iatrogenic; 56.7% were delivered for NEB indications. Women with NEB deliveries were older (30.0 vs 28.6 years, P = .001), and more likely to be pregnant with twins (18.8% vs 7.9%, P < .001), have private insurance (80.3% vs 59.0%, P < .001), or have a second complicating factor (27.5% vs 10.1%, P < .001). A total of 56% of EB deliveries resulted in NICU admissions. After controlling for confounders, early gestational age (34 vs 36 weeks: odds ratio, 19.34; 95% confidence interval, 4.28-87.5) and mode of delivery (cesarean: odds ratio, 1.88; 95% confidence interval, 1.15-3.05) were most strongly associated with NICU admission.

Conclusion: Over half of nonspontaneous late preterm births were NEB. EB guidelines are needed.

MeSH terms

  • Adult
  • Cesarean Section / adverse effects*
  • Evidence-Based Medicine
  • Female
  • Humans
  • Infant, Newborn
  • Infant, Premature
  • Infant, Premature, Diseases / etiology*
  • Intensive Care Units, Neonatal*
  • Labor, Induced / adverse effects*
  • Pre-Eclampsia / diagnosis*
  • Pregnancy
  • Premature Birth / etiology*
  • Retrospective Studies
  • Risk Factors