Hi Gwen, welcome to the forums!
There is a very, very small chance that you could get pregnant from having sex during your period.
A woman is fertile around ovulation, which is when the egg is released from the ovary. This generally happens around 14 days after your period starts, but this is not the same for every woman - it can vary between 12 and 16 days, and some women ovulate even later, or earlier, in their cycle than that.
Sperm may live up to 5 days in ideal conditions - therefore, doing the maths, if a woman's period lasts for 6 days, and she has sexual intercourse on the 6th day, and then the sperm live for their maximum of 5 days, and the woman ovulates early on, say, day 11 - then technically speaking, yes, it is possible for a woman to get pregnant from having sex during her period.
The chances are very low - but all the same, it IS definitely possible.
Are you trying to get pregnant, or trying to avoid it? I hope my answer helps, don't hesitate to ask if you have any further questions. If any other ladies have anything to add regarding this subject, please do feel free to offer your advice for Gwen.
Laura