While speaking with an 18-year-old woman who recently had intercourse, I inquired if she had used any contraception.

“Yes, I did. I used Coke.”

I said, “Coca-Cola, the soft drink?”

“Yes.”

“Diet or regular?” I asked.

She thought I was being funny. Not so. Believe it or not, researchers at the prestigious Harvard Medical School have studied the scientific basis for postcoital douching with Coke (seems a bit unseemly, does it not?) and concluded that Diet Coke has more of a spermicidal (sperm-killing) effect than regular Coke. They even addressed one of the great mysteries that has been plaguing mankind for years: which is more effective, new Coke or old Coke? These learned scholars found that new Coke was five times less potent than old Coke, but they did not investigate whether Coke was more effective than Pepsi. The Cola Wars thus rage on.

I won't argue with the bygone Coke advertising slogan, “Things go better with Coke,” but I will issue the following public service announcement to edify adventurous teenagers: don't rely upon Coke as a contraceptive. If you can believe the Harvard researchers—and who would have reason to doubt people who have dedicated their lives to the advancement of science?—Coke can kill sperm, at least in test tubes. It seems the scientists could not bring themselves to have recently inseminated women shake up a bottle of Coke and . . . um, let's just say that they declined to investigate the in vivo effects of douching with soft drinks. Since sperm can swim into the cervix (whereupon they are protected from annihilation by a spray of Coke) with surprising rapidity, they may be out of range before you finish shaking the bottle. And what else isn't the Surgeon General telling us?