Abstract
BACKGROUND: Timely contraceptive initiation is increasingly common, yet population trends by method and among subgroups with increased risk of unintended pregnancy are not well described. The impact of timing and type of contraceptive initiation on risk of unwanted pregnancy is unknown. METHODS: We used nationally representative cross-sectional data from 4 cycles of the National Survey of Family Growth, 2002-2015. We calculated outcomes from self-reported dates of sexual debut, contraceptive initiation, and unwanted pregnancy. We compared trends in timely contraceptive initiation (within 1 month of sexual debut) by method and by race and/or ethnicity and income. Using multivariable regression, we identified predictors of delayed contraceptive initiation. We compared the risk of unwanted pregnancy for delayed versus timely contraceptive initiation. RESULTS: We analyzed responses from 26 359 women with sexual debuts in 1970-2014. One in 5 overall and 1 in 4 African American, Hispanic, or low-income respondents reported delayed contraceptive initiation, which was associated with unwanted pregnancy within 3 months of sexual debut (adjusted risk ratio 3.7 versus timely contraceptive initiation; 99.9% confidence interval: 2.3-5.9; P < .001). Timely contraceptive initiation with less effective versus effective methods was not associated with unwanted pregnancy within 3 months. CONCLUSIONS: Delayed contraceptive initiation is more common among African American, Hispanic, and low-income women and is strongly associated with short-term risk of unwanted pregnancy. Pediatricians play a key role in making timely contraception available to adolescents at or before sexual debut. More research is needed to understand the importance of early contraceptive methods on pregnancy risk.