Up to 84% of women who undergo operative vaginal delivery receive neuraxial analgesia. However, little is known about the association between neuraxial analgesia and neonatal morbidity in women who undergo operative vaginal delivery. The authors hypothesized that neuraxial analgesia is associated with a reduced risk of neonatal morbidity among women undergoing operative vaginal delivery.
Using United States birth certificate data, the study identified women with singleton pregnancies who underwent operative vaginal (forceps- or vacuum-assisted delivery) in 2017. The authors examined the relationships between neuraxial labor analgesia and neonatal morbidity, the latter defined by any of the following: 5-min Apgar score less than 7, immediate assisted ventilation, assisted ventilation greater than 6 h, neonatal intensive care unit admission, neonatal transfer to a different facility within 24 h of delivery, and neonatal seizure or serious neurologic dysfunction. The authors accounted for sociodemographic and obstetric factors as potential confounders in their analysis.
The study cohort comprised 106,845 women who underwent operative vaginal delivery, of whom 92,518 (86.6%) received neuraxial analgesia. The proportion of neonates with morbidity was higher in the neuraxial analgesia group than the nonneuraxial group (10,409 of 92,518 [11.3%] vs. 1,271 of 14,327 [8.9%], respectively; P < 0.001). The unadjusted relative risk was 1.27 (95% CI, 1.20 to 1.34; P < 0.001); after accounting for confounders using a multivariable model, the adjusted relative risk was 1.19 (95% CI, 1.12 to 1.26; P < 0.001). In a post hoc analysis, after excluding neonatal intensive care unit admission and neonatal transfer from the composite outcome, the effect of neuraxial analgesia on neonatal morbidity was not statistically significant (adjusted relative risk, 1.07; 95% CI, 1.00 to 1.16; P = 0.054).
In this population-based cross-sectional study, a neonatal benefit of neuraxial analgesia for operative vaginal delivery was not observed. Confounding by indication may explain the observed association between neuraxial analgesia and neonatal morbidity, however this dataset was not designed to evaluate such considerations.
National obstetric guidelines indicate that adequate analgesia is a prerequisite for operative vaginal delivery (vacuum- or forceps-assisted).
Although more than 80% of operative vaginal deliveries in the United States are performed with neuraxial analgesia, the impact on neonatal outcomes remains unclear.
In analyses of national birth certificates from 2017, composite neonatal morbidity (low Apgar scores, assisted ventilation, seizures, neonatal intensive care unit admission, or neonatal transfer to another facility) was more common among 106,845 parturients receiving neuraxial analgesia versus those without neuraxial anesthesia (unadjusted composite outcome rate of 11.3% vs. 8.9%; adjusted relative risk, 1.19).
However, post hoc adjusted analyses focused on neonatal clinical outcomes (adjusted relative risk, 1.07; P = 0.054) or incorporating county of delivery information (adjusted relative risk, 1.09; P = 0.014) demonstrated questionable clinical or statistical significance.
A neonatal benefit of neuraxial analgesia for operative vaginal deliveries was not observed. Confounding by indication bias is a relevant possibility.