Nonspontaneous late preterm birth: etiology and outcomes.
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.


METHODS
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.


CONCLUSIONS
Over half of nonspontaneous late preterm births were NEB. EB guidelines are needed.
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
Cynthia
C
Gyamfi-Bannerman
Karin M
KM
Fuchs
Omar M
OM
Young
Matthew K
MK
Hoffman
D000328:Adult; D002585:Cesarean Section / Q000009:adverse effects*; D019317:Evidence-Based Medicine; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000209:etiology*; D007363:Intensive Care Units, Neonatal; D007751:Labor, Induced / Q000009:adverse effects*; D011225:Pre-Eclampsia / Q000175:diagnosis*; D011247:Pregnancy; D047928:Premature Birth / Q000209:etiology*; D012189:Retrospective Studies; D012307:Risk Factors