Measuring sex-selective abortion: How many women abort?

Current measurement of sex-selective abortion is based on observing an imbalance be tween the sex ratio at birth and the natural sex ratio, providing us with the number of missing female foetuses. However, this measure does not tell us how widespread this phenomenon is, i.e., how many women abort, which will not be equal to the number of sex-selective abortions if there is repeated sex-selective abortion. In this paper, we show that the number of women that abort between two consecutive births and whether they do so repeatedly can be inferred using sex ratios and information on birth spacing. We apply our model to Indian DHS data to estimate how many women abort and to assess whether they do so repeatedly between two births. The results depend on the birth order and siblings composition: For example, we find that women whose first born is a girl abort at most once before the birth of the second child, i.e., (almost) none of them abort a second time if again pregnant with a girl after a first abortion. In contrast, we find evidence of repeated sex-selective abortion before the birth of the third child among women whose first two children are girls. We also introduce a novel constrained maximum likelihood estimator that imposes a (set of) random constraint(s) and that may be of independent interest.