1. Ventura S, et al. Estimated pregnancy rates and rates of pregnancy outcome for the United States, 1990–2008. National Vital Stat Rep. 2012;60(7):1–21.
2. Mosher WD, Jones J, Abma JC. Intended and unintended births in the United States: 1982–2010. Natl Health Stat Rep. 2012;55:1–28.
3. Abma J, Martinez G, Copen C. Teenagers in the United States: sexual activity, contraceptive use, and childbearing, national survey of family growth 2006–2008. Vital Health Stat. 2010;23(30):1–47.
4. The healthcare costs of having a baby. Thomson Healthcare; 2007.
5. Wier LM, Andrews RM. The national hospital bill: the most expensive conditions by payer, 2008. Statistical brief #107. Healthcare Cost and Utilization Project (HCUP). Rockville: Agency for Healthcare Research and Quality; 2006.