Schalet’s most interesting assertion is that “the American boys I interviewed seemed more nervous about the consequences of sex than American girls.” It’s not clear if she interviewed girls as well as boys, but she offers this further point of comparison: “The 2002 National Survey of Family Growth found that more than one-third of teenage boys, but only one-quarter of teenage girls, cited wanting to avoid pregnancy or disease as the main reason they had not yet had sex.”

Given that nature imposes the physical burden of pregnancy on the female of the species, that sounds counterintuitive. And it’s possible that some of the boys in the survey, mindful of what Schalet quotes another sociologist as calling “the stigma of virginity,” are rationalizing away their lack of success with girls by chalking it up to prudence.

At the same time, there is good reason for males (men as well as boys) to be more fearful of sex than females. Contemporary reproductive technology and law place all the burden for unwanted pregnancy on them. Between the pill and abortion, women have complete control over the reproductive process. They can avoid or end any unwanted pregnancy, and the man involved has no say in the matter. In Planned Parenthood v. Casey (1992), the U.S. Supreme Court went so far as to hold that a married woman has the constitutional right to abort her husband’s child without even telling him.