Declining Perinatal and Under-5 Mortality Amid Rising Recorded Neonatal Morbidity in Kazakhstan, 2019–2025: A National and Regional Ecological Study

Kazakhstan has reduced perinatal and child mortality over the past decade, but much less is known about the health of the children who now survive. We analysed national routine health statistics for 2019–2025 covering 15 demographic, pregnancy, mortality and registered morbidity indicators, plus the lowest and highest regional values for six paediatric disease groups in 2025. Trends were estimated by ordinary least squares with HC3 robust standard errors, Theil–Sen slopes and Kendall’s tau. Possible changes in slope were explored with single-joinpoint regression and checked by leaving out one year at a time, and associations were examined after removing the linear calendar trend. Sensitivity analyses excluded the pandemic years 2020–2021 and the provisional year 2025. Stillbirth fell from 8.8 to 6.4 per 1000 total births (−27.3%), perinatal mortality from 11.4 to 8.0 (−29.8%), infant mortality from 8.37 to 5.85 (−30.1%) and under-5 mortality from 10.69 to 8.10 per 1000 live births (−24.2%). Registered neonatal morbidity rose every year, from 113.5 to 187.9 per 1000 live births (+65.6%; slope 13.45 per year, 95% CI 10.26 to 16.64), with little change when 2020–2021 were excluded. Registered disease rates among children under 5 reached a low point in 2021–2022 and then rose again, a pattern that changes in the share of infants could not explain. Seven annual observations could neither confirm nor exclude a link between falling mortality and rising registered morbidity. Recorded regional values differed several-fold. The cause of this variation is unclear: the published data cannot separate registration practice from real differences in morbidity, age structure, migration or chance.