title: Chorioamnionitis does not affect fetal urine production in patients with premature rupture of membranes.
abstract: The objective of this study was to evaluate fetal urine production rate in patients with premature rupture of membranes in the presence or absence of chorioamnionitis and to determine its clinical usefulness. Fetal urine production was evaluated in 30 women between 24 and 39 weeks' gestational age with ruptured membranes. Fetal bladder measurements were determined every 3-5 min for 30-90 min. Chorioamnionitis was defined by both clinical criteria and histological examination of the placenta. The last determination of fetal urine production rate prior to delivery was compared in patients with and without histologic and/or clinical chorioamnionitis. Fetal urine production rate was corrected for gestational age using birth weight prior to analysis. A total of 96 assessments of fetal urine production were performed (range 1-16 per patient). Twelve subjects (40%) had no evidence of chorioamnionitis (group 1), 10 (33%) had histologic chorioamnionitis alone (group 2), and eight (27%) had both clinical and histologic chorioamnionitis (group 3). The mean (+/- SD) urine production rates in these groups were 9.43 +/- 3.15 ml/kg/hr, 10.65 +/- 3.43 ml/kg/hr, and 9.97 +/- 2.81 ml/kg/hr, respectively. The difference in fetal urine production rate between the three groups was not statistically significant. A power analysis revealed that individual group sizes were adequate to document a 50% increase in fetal urine production rate with a type II error of < 10%. There were no documented cases of fetal infection based on neonatal cultures. The presence of histologic or clinical chorioamnionitis does not significantly affect fetal urine production in patients with premature rupture of membranes. The prospective assessment of fetal urine production rate does not appear to be clinically useful as an early indicator of chorioamnionitis.
authors.affiliation: Department of Obstetrics and Gynecology, University of Illinois at Chicago 60612-7313, USA.
authors.forename: T M
authors.initials: TM
authors.lastname: Nguyen
authors.forename: W J
authors.initials: WJ
authors.lastname: Meyer
authors.forename: D W
authors.initials: DW
authors.lastname: Gauthier
authors.forename: T
authors.initials: T
authors.lastname: Myles
mesh_terms: D002821:Chorioamnionitis / Q000150:complications*; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000150:complications* / Q000503:physiopathology; D005333:Fetus / Q000502:physiology*; D005865:Gestational Age; D006801:Humans; D011247:Pregnancy; D014554:Urination