Sexual intercourse during menstruation is pretty safe and normal, as long as you are engaging in safe and barrier-protected sexual intercourse. The same applies to oral sex. However, because the menstrual blood might contain STD bacteria or viruses, it is essential that you and your partner both use appropriate protection, such as a dental dam throughout oral sex as well as a condom, all the time during the intercourse.





But, at least theoretically, there is a chance that you might catch an infection while having barrier-unprotected sex during menstruation, because the external uteral ostium is pretty opened during this time of month, expelling blood and tissue outside, thus making the uterus more susceptible to infection. Moreover, various women who have a naturally shorter menstrual cycle (of 21 days from the beginning of one menstruation ‘till the beginning of the next) might even get pregnant while menstruating (because their ovulation day is the 7th day of menstruation onset, /- 3 fertile days). These are two more reasons to use a barrier-method (condom) for contraception as well as STI and other infections prevention, in order to make sex while menstruating-safe.