The burden of and factors associated with misclassification of intrapartum stillbirth: Evidence from a large scale multicentric observational study

Abstract

Introduction: Global estimates suggest 2.6 million stillbirths and 2.5 million neonatal deaths occur annually worldwide. The majority of these deaths occur in low resource settings where analysis of health metrics and outcomes measurements may be challenging. We examined the misclassification of documented intrapartum stillbirth and factors associated with misclassification.

Material and methods: A prospective observational study was performed in 12 public hospitals in Nepal. Data were extracted from the medical records of all births that occurred during the 6-month period of the study. For the study purpose, we classified birth outcome based on the presence of fetal heart sound (FHS) at admission and use of neonatal resuscitation. The health worker-documented intrapartum stillbirths were considered potentially misclassified when there were FHS present at admission and no resuscitation initiated after birth. The association between potentially misclassified intrapartum stillbirth and complications during labor, birthweight and gestational age was assessed using Pearson's chi-square test, bivariate and multivariate logistic regression.

Results: A total of 39 562 mother-infant dyads were enrolled in the study, all of whom had FHS at admission. Among the 391 intrapartum stillbirths recorded during the study, 180 (46.0%) of them had FHS at admission with no resuscitation initiated after birth and were considered potentially misclassified intrapartum stillbirths. Among these potentially misclassified intrapartum stillbirths, 170 (43.5%) had FHS present 15 minutes before birth and 10 had no FHS 15 minutes before birth Among the potentially misclassified intrapartum stillbirths, 23.3% had complications during labor, 93.3% had birthweight less than 2500 g and 90.0% were born preterm. The risk of intrapartum misclassification was nearly four times higher among low birthweight babies (adjusted odds ratio [aOR] 3.5, 95% confidence interval [CI] 1.8 to 7.0, P < 0.001) and five times higher among preterm babies (aOR 5.3, 95% CI 3.0 to 9.3, P < 0.001).

Conclusions: We estimate that 46% of intrapartum stillbirths were potentially misclassified intrapartum stillbirths. Improving quality of both FHS monitoring and neonatal resuscitation as well as measurement of the care will reduce the risk of potentially misclassified intrapartum stillbirth and consequently intrapartum stillbirth.

Keywords: Nepal; fetal heart rate monitoring; fetal heart sound; intrapartum stillbirth; measurement; misclassification; newborn resuscitation.