Many people ask: Can you be on your period and get pregnant? The simple answer is 'Yes - It is possible to get pregnant on your period'. However, this can only happen IF you have very early ovulation, since unprotected sex during ovulation is the best time to conceive.
You can also become pregnant during a non-menstrual bleed (anovulatory bleed) if you ovulate during, or directly after, the bleed. The only way to tell the difference between menstrual and non-menstrual bleeding is by confirming ovulation before the bleed, which you can do using a basal body thermometer or with a fertility monitor.