Some interesting research from the Guttmacher Institute, per ABC News:

The act of withdrawal — the male pulling out before ejaculation — is a long controversial method of birth control, one many sex education classes have condemned as risky.

But [researcher Rachel K.] Jones’ findings, based on several studies and data from the Guttmacher Institute , a nonprofit organization focused on sexual and reproductive health where she is a senior research associate, were just the opposite.

Her studies found that in perfect use — meaning the man pulls out every time — withdrawal has a 4 percent failure rate, as compared to condoms, which have a 2 percent failure rate.

“But nobody’s perfect,” said Jones, who published her commentary in the June issue of Contraception magazine.

In typical use, when used consistently and correctly, coitus interruptus and condoms have an 18 and 17 percent failure rate, respectively.

Please note the researcher’s distinction between “perfect use” and “typical use,” because most sex-ed advocates prefer to harp the “perfect use” numbers in making the case that condoms are the perfect panacea for preventing kids from suffering the consequences1 of premarital sex, which therefore become easier to bear than the consequences of abstinence.2


Notes

1. These consequences are assumed to be only physical ? not emotional. Furthermore, the physical consequences are assumed only to be related to pregnancy. Sure, there is discussion of venereal diseases, but when condoms are discussed in terms of safety, it is in the context of pregnancy, although an impression may be allowed to take that condoms are safe in prevention of venereal disease as well. It depends upon your definition of “safe.” They are, after all, in “perfect use”
safer than using nothing:

[The CDC’s] fact sheet on “Male Latex Condoms and Sexually Transmitted Diseases” notes first that abstinence or staying in a long-term, mutually monogamous relationship with an uninfected partner is the best method of avoiding STDs. Afterwards, for “persons whose sexual behaviors place them at risk of STDs,” it cites the risk-reducing measures of “correct and consistent use” of condoms ? and after citing that “condom use cannot guarantee absolute protection against any STD,” it stresses again that condoms must be used “correctly and consistently.” Incorrect use “diminish[es] their protective effect,” and inconsistent use “can lead to STD transmission because transmission can occur with a single act of intercourse.”

[T]he CDC have also noted, “condoms are more likely to break during anal sex than during vaginal sex. Thus, even with a condom, anal sex can be risky.”

A pregnancy-prevention failure rate of 17 percent is statistically the same as the hole-in-the-head-prevention failure rate in Russian Roulette. Consider, however, that pregnancy isn’t a necessary consequence of sperm transmission; infection may be another matter. If condoms in “typical use” are only 83 percent effective in preventing pregnancy, just how less effective are they in preventing STDs?

2. It is assumed that kids have no ability to withstand “the urge,” and therefore teaching them that the only safe approach to sexual activity isn’t abstinence save in marital monogamy is foolish and dangerous. Given those assumptions, the educational goal becomes teaching that safety is in condom use, and therefore that it is foolish and dangerous to question condom effectiveness or promote responsible behavior.

Essentially, kids can’t be expected to avoid sexual activity, but they can be expected to use condoms perfectly.