It is very harmful to have intercourse during vacation. It is necessary to limit intercourse during vacation, otherwise the following hazards may occur: 1. inflammation: intercourse during vacation may lead to inflammation, such as vaginitis, pelvic inflammatory disease or adnexitis, etc. The menstrual blood is more during the vacation period, when intercourse, because the blood is a good culture environment for the growth of bacteria, easily trigger bacterial infection, naturally prone to induce all kinds of gynecological inflammation; 2, endometriosis: intercourse during the vacation period, may also lead to endometriosis occur. Having intercourse during vacation may lead to the reflux of menstrual blood to the pelvic cavity, which in turn causes the planting of menstrual blood in various parts of the pelvic cavity, resulting in the creation of corresponding lesions and the gradual formation of endometriosis. Endometriosis may cause patients to suffer from dysmenorrhea, painful intercourse and even serious consequences of infertility; 3. Other adverse consequences: Some women consider the period of their vacation as a safe period and have intercourse during this period without effective protection, which leads to pregnancy. If the pregnancy is not planned, abortion is needed. Abortion may cause damage to the endometrium, thus inducing further uterine adhesions, less menstrual flow, and even infertility.