Fertility rates and abortion rates: simulations of family limitation.

A computerized model that simulates reproductive events during the childbearing years of a cohort of women is used to analyze the impact of contraception and induced abortion on fertility. Four different reproductive regimens are investigated: (2) contraception only, (2) abortion only, (3) abortion as a backstop to contraception, and (4) combinations of abortion and contraception. It is concluded that in historical as well as in modern populations, levels of fertility near replacement are unlikely to be obtained without the use of induced abortion.