Differential pattern of birth intervals in Bangladesh

Abstract

Findings from this 1989 Bangladesh nationally representative Contraceptive Prevalence Survey reveal that the survival status of the index child was a strong factor in explaining differences in birth spacing. The effect of mortality of the index child at the infant stage was shortening of the birth interval. The effect was weaker for child mortality. The age of the mother at child birth had the next strongest effect on birth spacing. Increases in maternal age at birth were associated with increases in birth interval. Explanatory variables that had little influence on birth spacing were maternal educational status, sex of the index child, residence, and birth order. The data pertain to open and closed birth intervals during 1984-89. There were 11,034 birth intervals, of which 36% were closed birth intervals. The analysis included the distribution of closed subsequent birth intervals among different subgroups and the study of the differences. The product-limit approach for estimating the survival function was used in the analysis of both mean closed and open birth intervals. About 75% of birth intervals among women aged under 35 years ranged 13-24 and 25-36 months. About 66% of birth intervals among women aged over 35 years lasted 13-35 months; 19-24% lasted over 3 years. About 25% of births occurred within 12 months after women experienced the death of an infant. Only 5% of births occurred within 12 months among women without a prior index child death. About 50% of women had a subsequent birth within 13-24 months after the death of the index child. The product-limit estimates confirmed that the death of an index child during infancy was a strong determinant of a short subsequent birth interval.