Background Low birth weight (LBW) and preterm birth are leading causes of under-five and neonatal mortality globally. Data about the timing of death and outcomes for LBW and preterm births are limited in Ethiopia and could be used to strengthen neonatal healthcare. This study describes the incidence of neonatal mortality rates (NMR) stratified by newborn size at birth for gestational age and identifies its predictors at five public hospitals in Ethiopia. Methods A prospective follow-up study enrolled 808 LBW neonates from March 2017 to February 2019. Sex-specific birthweight for gestational age percentile was constructed using Intergrowth 21st charts. Mortality patterns by birthweight for-gestational-age-specific survival curves were compared using the log-rank test and Kaplan-Meier survival curves. A random-effects frailty survival model was employed to identify predictors of time to death. Results Among the 808 newborns, the birthweight distribution was 3.2% <1000 g, 28.3% <1500 g, and 68.1% <2000 g, respectively. Birthweight for gestational age categories were 40.0% both preterm and small for gestational age (SGA), 20.4% term SGA, 35.4% appropriate weight for gestational age, and 4.2% large for gestational age (LGA). The sample included 242 deaths, of which 47.5% were both preterm and SGA. The incidence rate of mortality was 16.17/1000 (95% CI 14.26–18.34) neonatal-days of observation. Neonatal characteristics independently related to increased risk of time-to-death were male sex (adjusted hazards ratio [AHR] 3.21 95% CI 1.33–7.76), born preterm (AHR 8.56 95% CI 1.59–46.14), having been diagnosed with a complication (AHR 4.68 95% CI 1.49–14.76); some maternal characteristics and newborn care practices (like lack of effective KMC, AHR 3.54 95% CI 1.14–11.02) were also significantly associated with time-to-death. Conclusions High mortality rates were measured for low birthweight neonates–especially those both preterm and SGA births–even in the context of tertiary care. These findings highlight the need for improved quality of neonatal care, especially for the smallest newborns.

ObjectivesThis study aimed to determine the prevalence of small-for-gestational-age (SGA) and appropriate-for-gestational-age (AGA); compare variations in multiple risk factors, and identify factors associated with SGA births among preterm babies born <2000 g.DesignCross-sectional study.SettingThe study was conducted at five public hospitals in Oromia Regional State and Addis Ababa City Administration, Ethiopia.Participants531 singleton preterm babies born <2000 g from March 2017 to February 2019.Outcome measuresBirth size-for-gestational-age was an outcome variable. Birth size-for-gestational-age centiles were produced using Intergrowth-21st data. Newborn birth size-for-gestational-age below the 10th percentile were classified as SGA; those>10th to 90th percentiles were classified as AGA; those >90th percentiles, as large-for-gestational-age, according to sex. SGA and AGA prevalence were determined. Babies were compared for variations in multiple risk factors.ResultsAmong 531 babies included, the sex distribution was: 55.44% males and 44.56% females. The prevalences of SGA and AGA were 46.14% and 53.86%, respectively. The percentage of SGA was slightly greater among males (47.62%) than females (44.30%), but not statistically significant The prevalence of SGA was significantly varied between pre-eclamptic mothers (32.42%, 95% CI 22.36% to 43.22%) and non-pre-eclamptic mothers (57.94%, 95% CI 53.21% to 62.54%). Mothers who had a history of stillbirth (adjusted OR (AOR) 2.96 95% CI 1.04 to 8.54), pre-eclamptic mothers (AOR 3.36, 95% CI 1.95 to 5.79) and being born extremely low birth weight (AOR 10.48, 95% CI 2.24 to 49.02) were risk factors significantly associated with SGA in this population.ConclusionPrevalence of SGA was very high in these population in the study area. Maternal pre-eclampsia substantially increases the risk of SGA. Hence, given the negative consequences of SGA, maternal and newborn health frameworks must look for and use evidence on gestational age and birth weight to assess the newborn’s risks and direct care.