Perinatal risk factors for low and moderate five-minute Apgar scores at term

Abstract

Objective: To evaluate the specific maternal and perinatal variables associated with a low (≤3) or moderate (4-6) Apgar score, compared to a high (≥7) score.

Study design: This was a retrospective, cohort study of 58429 term singleton babies born at the Mater Mother's Hospital in Brisbane, Australia in 2007-2013. Maternal demographics, socio-economic status using the Australian Socioeconomic Index for Areas (SEIFA) score, obstetric factors, and birth outcomes were compared for neonates grouped into three categories based on their five-minute Apgar: low (≤3), moderate (4-6) and high (≥7). The low- and moderate-score cohorts were individually compared to the high-score cohort using both univariate and multivariate analysis.

Results: Logistic regression analysis confirmed that of the variables analysed, only maternal public insurance status (OR 2.1, 95% CI 1.5-3.1), breech presentation (OR 2.4, 95% CI 1.1-4.6), other non-cephalic presentation (OR 9.5, 95% CI 2.2-25.4), intramuscular narcotic use (OR 2.3, 95% CI 1.5-3.5), and presence of meconium (OR 3.7, 95% CI 2.5-5.4) were significantly associated with low Apgar scores. Variables significantly associated with a moderate score were: SEIFA ≤50th centile (OR 1.6, 95% CI 1.2-2.0) and 61st to 70th centile (OR 1.31, 95% CI 0.9-1.8) categories, maternal public insurance status (OR 2.7, 95% CI 2.2-3.3), nulliparity (OR 2.0, 95% CI 1.7-2.5), emergency caesarean birth (OR 2.6, 95% CI 2.1-3.2), instrumental birth (OR 2.3, 95% CI 1.9-2.9), and presence of meconium (OR 2.6, 95% CI 2.1-3.2).

Conclusions: Factors associated with low and moderate Apgar scores vary in type and degree of influence. Distinctions in the perinatal background can help predict newborn compromise and accelerate delivery of care.

Keywords: Apgar score; Breech; Caesarean section; Intrapartum outcomes; Malpresentation; Mode of birth.