Epidemiology of unintended pregnancy and contraceptive use.

Almost all women are at risk for unintended pregnancy throughout their reproductive years. However, adolescents, formerly married women, and women of low socioeconomic status are at greater risk for contraceptive nonuse and for contraceptive failure; thus they are also at greater risk for unintended conceptions. Of the 6.4 million pregnancies occurring in the United States in 1988, more than half (56%) were unintended. An equal proportion of unintended pregnancies end in abortion (44%) as with birth (43%), and both options have great personal and social consequences. The level of unintended pregnancy appears to have increased during the last decade after consistent decreases since the early 1960s. Decreasing both the periods of contraceptive nonuse and contraceptive misuse will help lower the rate of unintended pregnancy in this country.