Identification of risk-factors for early sexual intercourse is essential for informed design of programs to prevent teenage pregnancy [1,2]. Compared to teens delaying first sex until later adolescence, sexually active young teens are less likely to use condoms or other birth control [3], have on average more sexual partners, including multiple concurrent partners [4], and consequently are at increased risk of sexually transmitted infection and early pregnancy [5,6]. Teenage childbearing is in turn associated with a host of negative consequences to mothers and their children, with costs to society also documented [7].
