When can a girl get pregnant after sex?

A girl can get pregnant after having sex if she is ovulating and sperm fertilizes an egg. Ovulation typically occurs around 12-16 days before the start of a girl's next menstrual period. Sperm can live inside a woman's body for up to 5 days, so if a girl has sex during this time frame, she could potentially get pregnant. It is important to note that every woman's menstrual cycle is different, so it is not always easy to predict when ovulation will occur. It is always best to use contraception if you are not ready to become pregnant.