1. Use of contraception in the United States: 1982–2008;Mosher;Vital Health Stat,2010
2. Current contraceptive use in the United States, 2006–2010, and changes in patterns of use since 1995;Jones,2012
3. Contraceptive methods women have ever used: United States, 1982–2010;Daniels,2013
4. Unintended pregnancy in the United States: incidence and disparities, 2006;Finer;Contraception,2011
5. The public costs of births resulting from unintended pregnancies: national and state-level estimates;Sonfield;Perspect Sex Reprod Health,2011