Yes, you can. Anytime a guy and girl have vaginal intercourse, pregnancy is possible.

Girls usually start ovulating, which means releasing eggs, during puberty. This typically happens between the ages of 9 and 13. Ovulation happens first and then, if an egg isn't fertilized by sperm, a period starts about two weeks later.
 

So, if you have vaginal sex and then ovulate for the first time, you could become pregnant. Since you've never had a period before, you won't even know you've ovulated and should be getting a period. That means it could take longer for you to suspect you might be pregnant.

Anytime a couple has unprotected intercourse, they are also at risk for STDs. Young women are especially vulnerable to infections in their cervix. Although many young women look grown up on the outside, they haven't finished growing on the inside, such as her cervix.

Maybe the better question, though, is whether a girl so young is ready for the responsibilities of sex. Many people would say no. Having sexual intercourse with another person is a heavy experience, both physically and emotionally. Often, it's better to wait until you're older and better able to handle the responsibilities of sex. You have your whole life. What's the rush?

If you want to make an appointment at a family planning clinic to be tested for pregnancy and/or STDs, to get emergency contraception, or to get a reliable method of birth control, you can find one in your area by looking in your local yellow pages under "family planning" or "clinics." You can also click here, or call 1-800-230-PLAN to be connected automatically to the Planned Parenthood health center nearest you.