irregular periods

I see you have not received a response. I am sorry, but I find your question confusing. I do not know what you mean by "white blood." Are you referring to a white vaginal or penile discharge?

It sounds like you are asking if it is safe to have unprotected sex during a certain part of your girlfriend's menstrual cycle. It is never safe to have unprotected sex. Your girlfriend can get pregnant on any day, including during her period.

It sounds like your girlfriend's period stopped after only 12 hours during her last two menstrual cycles. Buy a pregnancy test and politely ask her to follow the directions to take the test. It is possible for a woman to be pregnant and still seem to get her periods without realizing she is pregnant.

It sounds like your girlfriend's periods have been irregular for a year. I do not know how old she is or when she first started to get her periods. Ask her if she would like to talk to a doctor about her irregular periods. Sometimes irregular periods are a sign of serious, but treatable, medical problems.

Go buy condoms and use them according to the instructions that come with them. There are many kinds of condoms. You can try different types and sizes to see which ones you prefer.

Use a condom every time you have sex. Proper condom use will dramatically lower the chance that your girlfriend will get pregnant. Using condoms also dramatically lowers the risk that you or your girlfriend will get a sexually transmitted infection. Sometimes people do not know they have a sexually transmitted infection, so using a condom is always safest.

You and your girlfriend will enjoy sex much more when you do not have to worry so much about her getting pregnant or either of you getting a sexually transmitted infection.