The bladder pain in late pregnancy is due to many reasons, which may be related to uterine compression of the bladder, hormonal secretion changes, cystitis and other factors. 1. Uterine compression of the bladder: the embryo will fall into the pelvic cavity in late pregnancy and compress the bladder, easily causing bladder pain, which is a normal physiological manifestation, without special treatment. 2. Hormone secretion changes: hormone levels may change in late pregnancy, manifested by increased levels of estrogen and progesterone, thus causing bladder pain, usually after the end of pregnancy symptoms will be relieved on their own. 3. Cystitis: mainly related to the lack of attention to urinary system hygiene during pregnancy, pathogenic bacteria into the urinary system will repeatedly stimulate the bladder area, causing pain, and accompanied by frequent urination, urinary urgency and other symptoms. Bladder pain in late pregnancy for a night should also be alerted to be a symptom of impending labor. If the pain does not go away, it is recommended to consult a doctor in time, and then according to the diagnosis of a professional physician for targeted treatment.