The female has a stomachache, which may be due to changes in ovulation, pelvic inflammation, or torsion of ovarian cysts. If the female has a stomachache in the middle of two menstruations, it may be caused by the rupture of follicle during ovulation and the stimulation of peritoneum, accompanied by the sense of tummy dropping and anal distension, and the secretion will also increase significantly. Generally, it can return to normal in three to five days, so pay attention to rest. If it is in the non menstrual period, and it is in the non ovulatory period, the small stomach pain may be related to pelvic effusion, which needs to be examined by B-ultrasound, and the amount of pelvic effusion should be determined. If the pelvic effusion is more than 2.0cm, accompanied by small stomach pain, pelvic inflammation should be considered and corresponding anti-inflammatory treatment should be carried out.