Abortion rates reflect the optimization of parental investment strategies

Parental investment decisions in human beings, including infanticide, have usually been considered in relation to the postnatal survival probabilities of their children. A number of factors which influence parental ability an d willingness to invest in offspring have been identified from these studie s. Here we argue that at least some of the same factors which influence inv estment decisions postpartum also affect the decision to terminate a curren t pregnancy through voluntary abortion. We show that both female age and ma rital status influence the probability of abortion, with the key variable b eing the likelihood of future marriage. Thus, abortion procedures extend a woman's ability to manage her reproduction into the prenatal period.