What is the percentage of women that get pregnant while on their period?

"After one month of trying I became pregnant and had a beautiful healthy boy!"

"After over 7 years of trying to conceive and thousands of dollars spent on infertility treatments, I had actually succeeded to get pregnant the natural way without any drugs or medical intervention "

" I just wanted to say thank you for writing this program and for giving hope to women at my age. I am 46 and I am finally going to be a mother."
Best information and tips about help for pregnant women, help with pregnancy and pregnancy help
I know there is a very low chance of a woman getting pregnant while shes is on her period. (IE Having sex while menstruating) But is there any research done that shows an actual percentage? I’ve looked all over but I can’t find anything.

Im pretty sure it’s like 4-6%….it is really low though considering if you have sex on your most fertile days you only have a 20-25% chance of getting pregnant!