It's hard to always make good choices. We all have to make crucial decisions about things like school and work. And with the high rates of sexually transmitted diseases (STDs) and unplanned pregnancy, we have to make tough choices about sex, too. But when we make choices about sex under the influence of drugs or alcohol, many of us end up with tougher problems on our hands.

It's common knowledge that drinking and using drugs impairs our ability to make good decisions, but do we really understand how much it can affect our sexual experience? Nearly one-quarter (23 percent) of sexually active young people, ages 15 to 24, report having unprotected sex because they were drinking or using drugs at the time. And 29 percent say that because of alcohol and drug use, they did more sexually than they planned to, according to a recent national survey by the Kaiser Family Foundation.

Fourteen-year-old Cass, of Los Angeles, CA, is one of these young people. At a party last January, after a night of drinking, she had sex for the first time with a guy she just met. "We weren't going out. I'd only met him that night. … Losing my virginity just wasn't what I thought it would be," she says.

Cass wasn't on the Pill, and she and the guy didn't use a condom. Fortunately, unlike many of her peers, she didn't get pregnant or get an STD.

If sober, people like Cass might say "no" to sex when they don't want to have it, or practice safer sex by using contraception consistently and correctly. They might also feel more comfortable talking with a partner about sex and contraception before doing anything.

Reasons vary for why people use drugs and alcohol before making tough decisions about sex. Some feel that alcohol and drugs will help them relax, and their sexual experience will be eased or heightened. Others drink or get high without the expectation of having sex. Once intoxicated, it becomes harder to make conscious choices. This is what happened to Zoë, 16, of Vancouver, WA.

Last summer, Zoë started hanging out with Lisa, 16, an old friend from middle school.

"She'd made a lot of new friends. Most of them hung out every weekend getting drunk and passing out. I didn't think much of it at the time," she says.

But after meeting and becoming attracted to Joe, one of Lisa's friends, Zoë started drinking with them.

"We actually never kissed or made out sober - not even once," she says.

After a month of hanging out, she went on a camping trip with Joe, Lisa, and another guy.

"Even though I was a virgin, my mom handed me a condom. I rolled my eyes because I had no intention of losing my virginity," says Zoë.

But once at the camp, after drinks were consumed, things changed.

"We briefly talked - or mumbled - about the idea of having sex. We were both so drunk that we thought it was a good idea. I must have passed out because there are parts missing in what I remember. It scares me so much to think that there were probably hours that I don't remember. We didn't talk about it at all the next day or on the ride home. I still feel very used and disappointed," says Zoë.

But some young people do realize the risks of mixing sex, drugs, and alcohol. Emanuel, 15, of New Jersey, who sometimes drinks and smokes, knows that if he ever got too drunk, he'd probably end up making unhealthy decisions.

"I may end up having unprotected sex and not be in control of my actions," he says.

Since his control gets weaker under the influence, Emanuel plans to never get so drunk or high that he ends up putting himself or his girlfriend in danger.

Steps to Sober Thinking

Susan S. Witte, Ph.D., associate director of the Columbia University Social Intervention Group, in New York City suggests that the best way to avoid sexual risk-taking is to avoid alcohol and drugs.

"But if young people find themselves in sexually risky situations, they should be familiar with ways to protect themselves and talk to their sexual partners before having sex about the importance of using a condom and practicing safer sex," she says.

Just ask Zoë. Even though she brought a condom on her camping trip, she had unprotected intercourse with Joe. The condom slipped off during sex with him the first time and then, hours later, they had sex again without using one.

"I liked Joe, but I never would've have had sex with him if I'd been sober. I'm so lucky that I didn't get pregnant or get an STD. If you're going to drink and do something sexual, think about it first. Be careful and responsible, because you could end up making a choice or mistake that could change your life forever," she says.

Andrea Lee, 16, of Montclair, NJ, is an editor for SEX, ETC., the national newsletter and Web site written by teens, for teens, on sexual health issues, published by the Network for Family Life Education at Rutgers, The State University of New Jersey.

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