The Effects of Pregnancy Spacing on Whether Pregnancies Result in Live or Non-Live Birth Outcomes in Matlab, Bangladesh

Julie DaVanzo, RAND
Lauren Hale, Stony Brook University, State University of New York
Abdur Razzaque, ICDDR,B: Centre for Health and Population Research
Mizanur Rahman, Pathfinder International

We use a large, high-quality longitudinal dataset on around 65,000 pregnancy outcomes gathered over a period of more than twenty years from the MCH-FP Area of Matlab, Bangladesh, to estimate the effects of the lengths of interpregnancy intervals (IPIs) on pregnancy outcomes and pregnancy duration. We find that, compared with IPIs of 27-50 months in duration, shorter preceding intervals increase the risk that the index pregnancy will result in a non-live birth (particularly an induced abortion) and to some extent they also increase the likelihood of a premature live birth. IPIs less than 6 months in duration are associated with a 10-fold risk of an induced abortion, a 5.8-fold risk of miscarriage, and a 2.3-fold risk of a stillbirth compared to IPIs of 27-50 months. A similarly short IPI is associated with a 0.3-week reduction in gestation duration compared to IPIs of 27-50 months in duration for live births and stillbirths.