Coitus Interuptus: Et Tu, Brutus?

The first time I went to Cosco, I was thrilled. I spent half an hour meandering through the isles sampling every bite of Beenie-Weenie, EasyMac, and Chef Boyardee that I was offered. While this new alternative to eating out did provide me with a free lunch, it also left me nauseous, bloated, and gave me horrible cramps. My Cosco experience served as a rather pungent reminder that something free of charge is not necessarily void of consequences.

Perhaps my weakness for anything free is shared by my peers, which explains why one out of five college students cite pulling out as their primary form of birth control. Coitus Interuptus (the official name) is free, involves little planning and comes with one simple instruction: pull and pray. Although these are nice benefits, one must not forget the most important criteria for selecting a form of birth control: effectiveness. Coitus Interuptus fails 19 percent of the time in a "typical use" scenario, according to the US Food and Drug Administration. This means that 19 percent of the time, Coitus Interuptus results in pregnancy. Some might conclude that this strategy is therefore 81 percent effective. Eight out of ten isn't bad if you were purchasing a scratch card at Campus Convenience, but eight out of ten sucks when you are talking about pregnancy.

The 19 percent failure rate is due to both pre-ejaculatory fluids and the lack of ejaculatory control. Pre-ejaculatory fluid (precum) is the clear sticky substance that leaks out of the penis prior to ejaculation. This alkaline substance is produced in the bulbourethal gland and is originally semen-free. However, the straggling sperm that were left behind in a prior ejaculation can hitch a ride out in the precum. Thus precum often contains sperm.

In laymen's terms, this phenomenon can be described by the following quote: "sex is like basketball, you dribble before you shoot." And even if your dribble is semen-free, not everyone is able to shoot with the same control as Michael Jordan.

As much as orgasms can be predicted (a sensation known in the scientific world as "ejaculatory inevitability"), sometimes they sneak up on you. Your riding along worry free, then your girlfriend lets out the cutest little moan, and just when you're about to pull out... damn! Millions of tadpoles carrying your genetic material are launched out of Ol' One Eye.

Even if you are able to pull out in time, you may spit your boys all over the outside of her vagina, which still puts you in the danger zone. Sperm are tough little SOB's and are more capable of swimming upstream than salmon. They move up the vagina at rates of three to seven inches an hour and can stay alive for two days, although it only takes them two hours to reach their destination. Men have hiked up Mt. Everest, so it shouldn't seem too preposterous that semen can swim up the vagina. And though not every sperm is a bona fide mountain man, out of the 600 million that can be in a single ejaculation, it only takes ONE.

Coitus Interuptus would have served better as the name of a Roman general rather than a type of birth control. However, we cannot change history. What we can change is the future. Pulling out does not prevent you or your partner from contracting a venereal disease, and it's not a reliable way to protect against pregnancy. The pull and pray technique isn't a valid method of contraception, and it should not be used.

Of course, any advice must be placed within context. It's not a smart idea to jump out of an airplane, but if the plane is crashing anyway, you have nothing to lose. That is to say, one day you may find yourself engaging in unprotected sex, in which case pulling out is an acceptable last resort.

If you are truly too broke to purchase birth control, the University Health Center has five buckets of lubricated, spermicided, and baby-powdered fun waiting for you. Michelle Bowdler, Director of Health Services, has assured me that the receptionists will not yell at you for taking too many condoms, or call you names for picking up a dental dam. And yes, both the condoms and the dental dams are absolutely free.

E-mail questions to sex@tuftsdaily.com.