Early neonatal mortality is modulated by gestational age, birthweight and fetal heart rate abnormalities in the low resource setting in Tanzania – a five year review 2015–2019

Background: Early Neonatal mortality (ENM) (<7days) remains a signifcant problem in low resource settings. Birth asphyxia (BA), prematurity and presumed infection contribute signifcantly to ENM. The study objectives were to determine: frst, the overall ENM rate as well as yearly ENM rate (ENMR) from 2015 to 2019; second, the infuence of decreasing GA (<37weeks) and BW (<2500g) on ENM; third, the contribution of intrapartum and delivery room factors and in particular fetal heart rate abnormalities (FHRT) to ENM; and fourth, the Fresh Still Birth Rates (FSB) rates over the same time period. Methods: Retrospective cohort study undertaken in a zonal referral teaching hospital located in Northern Tanzania. Labor and delivery room data were obtained from 2015 to 2019 and included BW, GA, fetal heart rate (FHRT) abnormalities, bag mask ventilation (BMV) during resuscitation, initial temperature, and antenatal steroids use. Abnormal outcome was ENM<7days. Analysis included t tests, odds ratios (OR), and multivariate regression analysis. Results: The overall early neonatal mortality rate (ENMR) was 18/1000 livebirths over the 5 years and did not change signifcantly comparing 2015 to 2019. Comparing year 2018 to 2019, the overall ENMR decreased signifcantly (OR 0.62; 95% confdence interval (CI) 0.45–0.85) as well as infants ≥37weeks (OR 0.45) (CI 0.23–0.87) and infants <37weeks (OR 0.57) (CI 0.39–0.84). ENMR was signifcantly higher for newborns <37 versus ≥37weeks, OR 10.5 (p<0.0001) and BW <2500 versus ≥2500g OR 9.9. For infants <1000g / <28weeks, the ENMR was ~588/1000 livebirths. Variables associated with ENM included BW - odds of death decreased by 0.55 for every 500g increase in weight, by 0.89 for every week increase in GA, ENMR increased 6.8-fold with BMV, 2.6-fold with abnormal FHRT, 2.2-fold with no antenatal steroids (ANS), 2.6-fold with moderate hypothermia (all <0.0001). The overall FSB rate was 14.7/1000 births and decreased signifcantly in 2019 when compared to 2015 i.e., ...