What's the percent chance of getting pregnant on the first day of your period?

Menstruation: It is impossible if this is your normal period on time. Please, at sixteen, learn the basic facts of your body. Please learn how to prevent unwanted pregnancy. To get pregnant a female must be ovulating and at the same time be exposed to fresh semen. Ovulation is a process that every female should know about and be able to identify when it happens in the cycle.