Abdominal pain below the navel may be due to cystitis or bladder stones, which often occurs in people who drink too little water. If the pain occurs below the navel of a male, it may be caused by chronic prostatitis or a combination of prostatic hyperplasia. For females, abdominal pain below the navel is often related to pelvic inflammatory disease or ovarian cysts, which should be taken seriously, as it may pose a risk or affect pregnancy. Generally speaking, there are several clinical situations that may cause pain below the navel: 1. If the pain occurs below the navel of a male, it may be due to chronic prostatitis accompanied by prostatic hyperplasia. Prostatic hyperplasia can cause obstruction of the urethra, leading to difficulty in urination, and a large amount of urine accumulates in the bladder, causing pain and discomfort in the bladder. 2. Pain below the navel may be caused by bladder stones accompanied by bladder inflammation, which is more common in patients who drink less water and form stones in the bladder. The stones repeatedly stimulate the bladder wall, causing lower abdominal pain, urgency, and frequent urination. 3. Abdominal pain below the navel in females may be due to gynecological inflammation such as pelvic inflammatory disease or pyosalpinx, which is more common in patients with frequent sexual activity. Poor hygiene of the perineal area allows external bacteria to invade, causing acute infection. 4. Abdominal pain below the navel in females may also be due to ovarian cyst torsion. Larger ovarian cysts may undergo torsion during vigorous exercise, leading to acute ischemia and necrosis of the ovary, causing severe lower abdominal pain.