Obstetric risk factors for poor neonatal adaptation at birth

To identify obstetric risk factors of delivering a neonate with poor neonatal adaptation at birth.

Nested case-control study. Poor neonatal adaptation was defined for presence of at least: umbilical cord artery pH <7.10, base deficit ≥12 mmol/L, Apgar score at 1' ≤5. Controls were selected from the same population and matched with cases. The association between clinical parameters and poor neonatal adaptation was analyzed by logistic regression.

One hundred and thirty three women (2.1% of all live births) with a neonate presenting a poor neonatal adaptation were matched with 133 subsequent controls. Significant contributions for the prediction of poor neonatal adaptation were provided by maternal age ≥35 years (p ≤ .001, odds ratio (OR) 3.9 [95%CI: 2.3-6.8]), nulliparity (p ≤ .001, OR 3.3 [95%CI: 1.8-6]), complications during pregnancy (p = .032, OR 2.2 [95%CI: 1.1-4.4]), gestational age at delivery <37 weeks (p = .008, OR 5.2 [95%CI: 1.5-17.8]) and cardiotocography category II or III (p ≤ .001, OR 36.3 [95%CI: 16.5-80.1]). The receiver operative characteristic curve was 0.91 [95%CI: 0.87-0.95], and detection rates 82.7% and 89.5% at 10% and 20% of false positive rates, respectively.

Several obstetric risk factors before and during labor can identify a subgroup of newborns at higher risk of a poor neonatal adaptation at birth.