A stochastic model for the study of last closed birth interval with some biosocial components

We present a stochastic model to describe variation in last closed birth interval for women of a given marriage duration by parity as well as regardless of parity. The model is derived under some simplified assumptions relating to human reproduction process accounting for the non-exposure period in the beginning of the reproductive life caused by such biosocial components as adolescent sterility and temporary separation between the partners called as an inoperative period. We illustrate the model regardless of parity on an observed set of data taken from a rural area of northern India and estimate the risk of conception before and after the first birth.