Why Do Women Use Contraception?

Tom A. Moultrie, University of Cape Town
Ian M. Timaeus, London School of Hygiene and Tropical Medicine

Much of the demographic literature presumes that women use contraception to either limit family size or space births. This paper argues that women also use contraception to postpone pregnancy. Postponement is not synonymous with spacing but arises when women delay their next birth for reasons unrelated to the age of their youngest child. We demonstrate that postponement has a distinctive impact on the shape of birth interval distributions that differs from those of family size limitation, birth spacing, and a mixture of the two behaviours. Some populations, such as South Africa, have developed fertility regimes characterized by birth intervals far longer than can be accounted for by birth spacing. Postponement of births is most likely to become widespread in countries characterized by social unrest and dysfunctional institutions and those developed countries with particularly high opportunity costs of childbearing for women.