The demographic impact of abortion. Estimated to be one fifth of total fertility

: There is consensus among demographers that, in countries where abortion is illegal, its magnitude cannot be estimated directly and can be estimated indirectly only with great difficulty. Because of the difficulty of quantifying the practice of abortion in Mexico, its occurrence is neglected in discussions of the country's demographic problems. But apart from issues of women's rights or health consequences, it is necessary that the general population, politicians, and opinion leaders assess abortion in its relationship to fertility and population growth. Study in numerous countries with varying socioeconomic characteristics suggests that no country can achieve a population growth rate near 1% without recourse to induced abortion as a complement to effective contraceptive usage. Experience shows that no country has achieved a total fertility rate under 2.2 without abortion. Observation of the demographic transition suggests that there are three phases in the relative role of induced abortion. In the first, fertility levels are high in the absence of contraception, and abortion is practiced but is not responsible for most intrauterine mortality. At a second stage, abortion becomes very important as the population begins to control fertility but lacks access to effective contraception. In the third stage, use of effective contraception permits fertility to be controlled, and abortion is used when contraception fails or is not used. National surveys indicate that in the 1960s, most Mexican women had 7 children and fewer than 10% used contraception. At present, most Mexican women in union use effective contraception, but a significant proportion still do not. Women not using contraception but not desiring more children and women whose methods fail constitute a pool of potential abortion seekers. Computer simulation models employing data from national fertility surveys have been used to estimate the different combinations of contraception and abortion that result in observed or projected total fertility rates. Assuming that in Mexico at present, 60% of couples limit their fertility after two children, that the total fertility rate is 3, and that the level of effectiveness of contraception is 95%, the implied total induced abortion rate is approximately 0.7 abortions per women at the end of her reproductive life. This level represents around 20% of current fertility. The abortion rate will decrease with increases in contraceptive efficacy, but the sociocultural conditions of the population, qualitative characteristics of family planning programs, and current state of contraceptive technology will limit increases in contraceptive efficacy in the short term in Mexico.