What's wrong with third trimester frequency?

Pregnant women in early pregnancy bladder by the pressure of the enlarged uterus, will show frequent micturition, and then with the increase of the uterus, will exceed the pelvic, symptoms will ease. But to the third trimester because the fetal head into the basin after the pressure bladder, urethra, etc., some pregnant women will show frequent micturition and urinary incontinence, this is a physiological change, do not need to do special treatment. General fetal head into the basin, it means that soon after delivery, frequent micturition symptoms will disappear. Pregnant women, because of the oppression of the uterus, ureter will show expansion, even hydronephrosis; and pregnant women are prone to acute nephritis, are caused by physiological changes in pregnancy.