During 1989-1997, the percentage of women with delayed PNC or no PNC decreased from 25% to 18%, with improvement in both delayed PNC (from 22% to 16%) and in no PNC (from 2% to 1%). The decrease in no PNC during 1989-1997 resulted in an estimated 206,000 additional women entering PNC who may not have done so had the 1989 rate remained unchanged. Groups more likely to have delayed or no PNC during 1989-1997 included non-Hispanic blacks, Hispanics, women aged less than 20 years, women with less than 12 years of education, and multiparous women. However, those same groups generally had larger absolute improvements in delayed and no PNC during 1989-1997. For example, the prevalence of Hispanic women with delayed or no PNC decreased from 41% to 26%, and for women aged less than 20 years, from 47% to 32%.