The main purpose of having sex with a condom during menstruation is that menstrual blood will not contaminate the male genitals, so it may still cause the following consequences for women: 1. It can lead to the invasion of pathogenic bacteria and cause endometritis and cervical inflammation, which will cause recurrent lower abdominal pain, yellowing of the vaginal secretion or lumbosacral pain in the later daily life and may also be manifested as dribbling of the menstrual period. 2. 2, in the menstrual period even with a condom, will also cause sexual excitement, will lead to uterine contraction, which may make the menstrual blood down the fallopian tube and flow to the pelvis, will cause endometriosis may not only appear progressive aggravation of dysmenorrhea, in the clinic may also lead to infertility.