Underestimation of infant mortality rates in one republic of the former Soviet Union.

OBJECTIVES Kazakhstan's live-birth definition--that dates from the former Soviet Union (FSU) era--differs from that used by the World Health Organization (WHO). We studied the impacts of both live-birth definitions on the computations of the infant mortality rate (IMR) and maternal and child health (MCH) planning in Zhambyl Oblast, Kazakhstan. METHODS We interviewed caregivers and abstracted medical records to obtain birth weight and age-at-death information on infant deaths in Zhambyl Oblast from November 1, 1996, through October 31, 1997. Using the 2 indicators of birth weight and age at death, we created a matrix delineating the respective contribution to infant death (maternal health, newborn care, or infant care) for the cells. We then calculated the IMR, birth weight-specific IMR (BWS-IMR), and birth weight-proportionate IMR (BWP-IMR) for each cell. RESULTS The observed IMR in Zhambyl Oblast, in 1996--using the definition of a live birth from the FSU--was 32 per 1000 live births. The recalculated IMR--using the WHO definition--was 58.7 per 1000 live births. Computed estimates of the contribution to infant death, by the categories of maternal health, newborn care, and infant care, were 10%, 23%, and 67%, respectively, when using the live-birth definition from the Soviet era. These estimates shifted to 24%, 41%, and 35%, respectively, when using the WHO definition, yet only 8% of the Zhambyl Oblast MCH budget was earmarked to maternal health and newborn care, which we estimated accounted for 65% of infant deaths. CONCLUSIONS The live-birth definition commonly used in the FSU underestimated the IMR and undervalued the contributions to infant death by both maternal health and newborn care. We recommend that all republics of the FSU adopt the WHO live-birth definition so that the IMR can serve as a better indicator for MCH planning.