Can I get pregnant the first time I have sex?

Yes, you can. You can even get pregnant if you haven't had your first period yet but are going through puberty.

Pregnancy, or more correctly, conception, happens when a viable sperm enters a viable ovum (egg). Because eggs only live for 12 to 24 hours, sex has to occur around the time of ovulation for a pregnancy to occur - specifically, the five days before ovulation through to the day of ovulation. This is called the "fertile window" and reflects the lifespan of an ovum and the lifespan of sperm (around 5 days although, rarely, some sperm may last 7 days).

Sex that occurs before a first period could potentially result in pregnancy if ovulation occurs within five to seven days of the sex. And it has done, many times, as numerous teenagers will testify.

Ovulation in many women, and in particular teenagers, can also be hard to predict if menstrual cycles are irregular. This is why ANY stage of the menstrual cycle should be treated as a "risk period" for pregnancy until your cycles become predictable.

Pregnancy is not the only thing you need to consider before having sex. Sexually transmitted infections (STIs) are also prevalent; although the risk of transmission is greatly reduced by condom usage.