My girlfriend and I were having dry sex with no clothes on and i can't remember ever getting near her vagina when i ejaculated. However, she hasn't had her period yet and she was suppose to around this time. She said that cemen dies when it touches oxygen and that everything was o.k. Is this true?

Sperm do NOT die when in contact with oxygen. This is a myth. In reality, sperm can live for about twenty to sixty minutes in an inhospitable (outside of the body) environment.

Dry sex is a pretty low risk sexual activity, for both sexually transmitted infections and pregnancy. There is only a risk (for either) if there is an exchange of bodily fluids or any genital contact. That said, low risk does not mean NO risk.

Your risk for sexually transmitted infection is actually much higher than your risk of pregnancy. If you and your partner have not both been tested for sexually transmitted infections six months apart and are monogomous, you need to be using condoms and lubrication for all sexual contact (this means dry sex too). Using condoms greatly reduces your risks of both sexually transmitted infections and pregnancy.

Because there is such a low risk of pregnancy from this, I wouldn't suggest a pregnancy test at this time. If she's a week or more late AND her periods are normally regular, then I would suggest she take a pregnancy test.

You also really need to sit down and discuss what you would do in case of a pregnancy or infection. You need to negotiate healthcare, protection, and costs of both. It always seems easy at first glance, but there needs to be clear, open communication about it, and the ability to plan ahead.

We have quite a few articles here that I think you will find useful. Print them out and go over them with your girlfriend.

• What's the Risk? Easy Pregnancy Risk Assessments
• Ready or Not? The Scarleteen Sex Readiness Checklist
• Safe, Sound & Sexy: A Safer Sex How-To
• STI Risk Assessment: The Cliff's Notes
• Testing, Testing...