The Effect of birth spacing on childhood mortality in Pakistan.

Summary In this study retrospective data from the 1975 Pakistan Fertility Survey are used to examine the effects of birth spacing on infant and child mortality. The length of the preceding interval between live births emerges as a major determinant of mortality. The effect persists for rural and urban families, for children of uneducated and educated mothers, for both boys and girls, and for large and small families. The possibility that this relationship is the spurious consequence of data defects or of a common cause, such as early weaning, is examined but rejected. Once the length of the preceding interval is controlled, the average spacing of earlier births is found to be unrelated to survivorship. However, the length of the succeeding interval is significantly related to survivorship during the second year of life.