What’s the best way to respond when someone you’re involved with sexually asks how many people you’ve been with before?

Everyone has a different opinion on whether or not to disclose your “number.” Some say it’s nobody’s business and that you should never tell. Others insist that full disclosure is the only way. I say it depends on who’s asking, why they’re asking, and why it’s important for them to know.

There are three reasons why someone might ask:
1. to find out how risky you are
2. to compare levels of sexual experience
3. to know you more intimately

The fact is, the more sex partners a person has had, the greater their chances of getting a sexually transmitted disease. But your lifetime number does not predict your risk of having an STD right now. The number that matters is how many partners you’ve had since the last time you were tested for STDs. If that number is zero, all you need to say is that you’ve been tested and you don’t have any-thing. If it’s not zero, your partner deserves to know the number.

It’s normal to wonder if your partner is more, less, or equally experienced than you in the sack. When people get together to do other kinds of things, they’re usually up-front about how much experience they have. For instance, if you go out in a canoe with someone you haven’t canoed with before, you’d naturally tell each other about your canoeing experience — that helps decide which one of you should steer, how fast to paddle, and whether or not you’re likely to tip the canoe.

Usually it’s best to let someone know if they are going to be your first or second sex partner. I think that after number two, counting partners becomes less and less meaningful as a measure of experience. If asked, “a few” or “plenty” are perfectly good answers.

While it can be enough to sketch an outline of your sexual history for someone you’re seeing casually, when a romance turns into a real relationship, you should be more open about your sexual past.

Some couples decide it’s best if they don’t know each other’s numbers, and swear to never tell. I won’t presume to know what is best for every couple, but I think choosing to keep your sexual histories secret would make it hard to talk about sex — there would be so many things that could hint at the past you’d have to avoid talking about. As the relationships expert Dr. Carl Sagan said, “You have to know the past to understand the present.”

Being intimate with someone really is about sharing truths, past and present. The number of people you’ve had sex with is a big truth, and in a sexual relationship it’s key to understanding each other. If you’re afraid to confide facts, maybe you’re not ready for that degree of intimacy. But also realize that dishing on your past — and dealing with any jealousy, shame, and other weirdness that it might bring up — creates intimacy.

Or it wrecks your relationship. Ultimately, it’s a choice between risking a break-up and never really knowing the person who shares your bed.

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