[Limitations of infant mortality as a health indicator]

Infant mortality is usually accepted as a sensitive indicator of living conditions, and of the coverage and quality of health care in a specific country. However, the validity of this indicator in middle-income countries presents some important limitations. First, underegistration of infant deaths is a common feature. In second place, the national figures hide the great inequalities that may exist among different social sectors and regions. In this paper, the limitations of Mexico's infant mortality rate are analyzed. Underegistration is demonstrated by comparing infant mortality rates obtained from vital statistics data and national health surveys. Differences among social sectors are evident when specific infant mortality rates are compared. Inequalities have been increasing in the last years.