Study of urinary outflow in pregnancy

Anatomical and physiological changes in the urinary tract develop during pregnancy. These changes may affect the urinary outflow. Urinary symptoms may develop during pregnancy in previously asymptomatic patients. Most of these symptoms will vanish after delivery. Some of them remain and others will become worse in consecutive pregnancies. A study was designed to compare if there was any difference in the urinary outflow between pregnant and non-pregnant women. Changes in the urinary outflow at different gestacional ages were studies too. In general, the urinary volume is higher in pregnant than in non-pregnant patients. Having said this, during the pregnancy this volume decrease in the third trimester. Peak urinary outflow is higher in pregnancy, being statically significant during the second and third trimester. Opposite to the non-pregnant patient, peak urinary outflow does not decrease with urinary volumes over 500 ml in pregnant patients. Significant differences were not found in the mean urinary outflow in both groups.