First of all, it's tough, but you've got to do it--no matter how uncomfortable it makes you feel. It doesn't matter if your partner is your current honey, a casual fling, or someone you're no longer dating. You have to let him or her know about this infection. In many situations, it's impossible to know who gave the infection to whom.

If you've already had sex, you may have already infected your partner, and he or she needs to see a doctor. Your partner also needs to use protection if he or she is having sex with other people, so the infection isn't spread.

If you're thinking about having sex, your partner(s) have the right to know the risks, so they can make a decision. Tell your partner about your STD and what your doctor says about if and when it's safe to have sex. Of course, you'll need to practice safers like, like using condoms--no matter what. And it's best to abstain from sex until the infection or symptoms clear up.

So, how to tackle this tough job? Know the facts. The other person will likely have questions, so know as much as you can about the STD. Then, think about what you want to say to your partner or former partner and practice it with a friend, a counselor, or to yourself in front of a mirror. Then take a deep breathe and talk to the person in private.

Sylvia Mayorga's story, "How to Talk to Your Partner if You have an STD" may help you, too.

Many people will understand and be supportive. But some won't. Others might get angry. If you believe that your partner may become violent or vindictive, then don't tell him or her face-to-face. Your safety is important. Make a plan to tell them in a way that puts you out of harm's way, such as telling them over the phone, IM, e-mail or using the anonymous partner notification system at www.inspot.org.

You can read more about communicating with a partner through MTV's Web site, and telling a partner about your STD status at the American Social Health Association.

Have more questions about how to talk to your partner about STDs? Call the CDC's national STD hotline at 1-800-227-8922, open 24/7.