In rural Bangladesh, women’s mortality is not directly related to the total number of children they bear or to their pace of childbearing.1 Analyses based on Matlab Demographic Surveillance System data show, however, that each birth is associated with an elevated risk of death that extends for more than two years following the immediate perinatal period. In addition, the odds of death are positively associated with age and negatively associated with height and body mass index. The authors estimate that reducing lifetime exposure to the extended risk associated with individual births could lower mortality among reproductive-age women by approximately one-quarter.

Previous research on the association between women’s risk of mortality and various aspects of childbearing-for example, parity and the interval between births-has yielded mixed results. To investigate further the relationship between mortality and fertility, researchers examined data from 2,031 married women who had originally participated in a study on fertility conducted in the mid-to-late 1970s. That study had collected information on reproduction (e.g., pregnancies, terminations and births), maternal health (e.g., height, weight and body mass index) and child health each month for three years, as well as socioeconomic information (e.g., education and religion) at study entry. Women were then followed up as part of the Matlab Demographic Surveillance System, which records all births, deaths and migrations occurring each month. The researchers converted data into woman-years for each woman for each calendar year, beginning with the year of study enrollment and ending with the year of death or migration, or 1996; data from returning migrants were excluded from analysis.

Researchers examined data on the basis of age at the start of a given woman-year. By the end of the study period, the 2,031 women had contributed a total of 34,067 woman-years between ages 16 and 54-the age by which all women had completed childbearing. The average height of the women was about 148 cm and the average body mass index was 18.5. Roughly three-quarters (77%) of women had not received any schooling, and 13% were Hindu. By the end of follow-up, a total of 3,937 children had been born and 100 women had died. On average, women of reproductive age had had a total of five live births each and had given birth at a slightly faster pace than had women in Matlab in 1979 (rate ratio, 1.1).