The doctor told her that it was pelvic fluid and asked her to check again after her period. Xiao Yun was relieved to find out that there was no fluid after her menstrual period, when she was checked again with an uneasy heart. But she didn’t quite understand where this pelvic fluid came from. How did the fluid disappear on its own? Where does pelvic fluid come from? The pelvis of women is a fluid circulation system, the peritoneum is constantly secreting fluid, and the peritoneum is constantly absorbing fluid, so it is normal to have a small amount of fluid in the pelvis, called physiological pelvic fluid, do not be too nervous. However, if the ascites is moderate or above, it may be a pathological effusion and needs attention. 1, physiological pelvic fluid: because the pelvic cavity is the lowest part of the abdominal cavity in the body, when the abdominal cavity has exudate or leakage fluid will accumulate in the pelvic cavity, thus forming pelvic fluid, some women in ovulation or early pregnancy will have a small amount of fluid accumulation in the pelvic cavity. 2, pathological pelvic fluid: clinically most women’s pelvic fluid is caused by inflammation, the presence of inflammatory exudate in the pelvis. Other conditions such as ovarian tumors, endometriosis, tuberculosis, ectopic pregnancy, rupture of cysts and rupture of corpus luteum can cause pathological effusion. There are two other conditions that need to be distinguished: 1. Small amount of pelvic fluid during menstruation: Some women have a small amount of menstrual blood and endometrial debris flowing backwards into the pelvic cavity along the fallopian tubes during menstruation. Some women have backflow of menstrual blood due to cervical or uterine adhesions, cervical fibroids, deformities of the reproductive tract, or various other reasons, and pelvic effusion caused by this condition should be taken seriously. 2. Effusion caused by surgical operation. Surgery such as hysteroscopy or tubal lavage, which involves injecting drugs or fluids into the cervix from the cervical opening, may cause pelvic fluid. However, it does not matter as the fluid will be absorbed naturally by the peritoneum after a few hours or days. What are the symptoms of pelvic effusion? The majority of cases with a small amount of fluid do not have any symptoms, but those with a moderate amount of fluid or more may have symptoms, mainly abdominal pain and bloating. If it is accompanied by gynecological diseases, there will be corresponding symptoms of the disease. Does pelvic fluid need to be treated or not? The treatment of pelvic effusion is also based on the principle of differentiation. Physiological and surgical cases do not require treatment and will be absorbed naturally. Pathological pelvic fluid should be treated according to different causes, and if necessary, posterior vault aspiration should be performed to identify the nature of the fluid, such as those caused by ruptured cysts, ectopic pregnancy or ruptured corpus luteum, which require emergency surgery; those caused by pelvic inflammatory disease or tuberculosis should be treated with anti-inflammatory or anti-TB therapy and followed up regularly according to the doctor’s requirements. In short, it is important to go to a regular hospital and ask a specialist for symptomatic treatment according to the different causes.