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2. Centers for Disease Control and Prevention (CDC)Reproductive Health Web site20132014-12-17Unintended pregnancy preventionhttp://www.cdc.gov/reproductivehealth/UnintendedPregnancy/6dz2jh090
3. WindRMedia Center: News Release Web site201105192014-11-14Guttmacher InstituteNation pays steep price for high rates of unintended pregnancyhttp://www.guttmacher.org/media/nr/2011/05/19/index.html6dz35K8x5
4. Shifts in Intended and Unintended Pregnancies in the United States, 2001–2008
5. Unintended pregnancy in the United States: incidence and disparities, 2006