Wu S J, Tsai Y L, Hsieh B S
Department of Obstetrics and Gynecology, Taipei Municipal Women and Children Hospital, Taiwan R.O.C.
J Formos Med Assoc. 1991 Oct;90(10):932-5.
Sequential changes in plasma renin activity (PRA) and the plasma aldosterone (PA) level were studied prospectively in 101 patients at Taipei Municipal Women and Children Hospital from the 20th week of gestation to the 4th week postpartum. Average maternal age was 31.8 years old and average fetal birth weight was 3,235 g. The PRA and PA levels during pregnancy were higher than those of the normal nonpregnant women. PRA decreased gradually from the 20th week of gestation and dropped markedly after delivery. The PA level increased after the 20th week of gestation and peaked at the 32nd gestational week, then returned to the nonpregnancy level after delivery. A dissociation between the PRA and PA levels after the 28th week of gestation was observed. Possible causes for this dissociation are discussed. This study provides reference data on PA and PRA levels during the course of a normal pregnancy for use in further studies on abnormal gestation.
