Among a sample of adolescent virgins, those living at home with two parents were roughly 38% less likely to engage in sexual activity for the first time during the following year when compared to adolescents not living at home with two parents.

Source: "Friends’ religiosity and first sex." Adamczyk, A., Felson, J.
Social Science Research Vol. in press, Number . , 2006. Page(s) NA.

(HT: FamilyFacts.org)