It's not possible to get pregnant ON your period. It's possible if you have an early ovulation to get pregnant from sex you had while you were on your period, but it's not the same thing.
Anon at 12:10 You can NOT get pregnant anytime there is a penis in your vagina. An egg has to be there, and an egg is alive for a maximum of 24 hours a cycle. If you double ovulate it can be up to 48 hours, but that's it. We are not fertile all throughout our cycle. Men are the ones who are fertile 24/7. We are fertile for only a day or two per cycle.
Please, ladies, educate yourselves. People are going to get tired of me saying this, but get the book Taking Charge of Your Fertility by Toni Weschler. It will teach you all you need to know about your reproductive cycle. Hopefully some of you will buy the book. It is well worth the money. It's available on Amazon.com.
at 9:26 AM on May. 24, 2009