There is absolutely no 'safe' time to have sex, if you are talking about getting pregnant. Ovulation generally occurs around the 14th day of your cycle (the 1st day of your cycle is the first day of menstruation). However, you may ovulate many days before or many days after that. If you do not want to get pregnant, always use some sort of contraception. If you are talking about STIs...again, there is no 'safe' time to have sex. HIV and infections are easily passed via blood contact, so you may be more likely to transfer your infection/virus to your partner if you are bleeding.If, however, you are wondering if it is safe to have sex in general while you are bleeding, the answer is yes. For hygienic reasons, you may want to be in the shower/bath or put down some sort of towel so that you don't stain furniture/your bed. Provided neither of you have STIs, neither you nor your partner will become sick from doing it during your period.