Measurement Of Urine Production Rate By Three-dimensional Ultrasonography In Fetuses With Digestive Tube Obstruction, Central Nervous System Defects, Hypertension Disorders In Pregnancy And Intrautrine Growth Restriction

Objective To evaluate the changes of urine production rate(UPR) in the fetuses withdigestive tube obstruction and central nervous system(CNS) defects.Methods (1)15women with normal singleton pregnancy were selected for thereproducibility.Fetal bladder volume was measured using the virtual organcomputer-aided analysis(VOCAL) technique by three-dimensional ultrasonography.Bland and Altman’s graphical approach was used to investigate the agreementbetween intra-and inter-observer variability， and the intraclass correlationcoefficient(ICC)of intra-and inter-observer were calculated.(2)58women with normalsingleton pregnancy at15～38weeks’ gestation were selected as the control group，and10consecutive fetuses with digestive tube obstruction and20consecutive fetuseswith CNS defects in the same period were selected as the case group.5fetuses withanencephalia were considered as the subgroup of CNS defects.All cases in the casegroups were complicated with polyhydramnios. Fetal bladder volume was measuredwithin a2～5minute interval using VOCAL technique by three-dimensionalultrasoound，and fetal UPR was calculated using the equation UPR (ml/h)=(thesecond bladder volomn-the first bladder volomn)×60/time interval（min）.Measurethe UPR in all groups respectively.To adjust for gestational age (GA)， UPR wastransformed to Z-score using the formulae： Z-score=(measured UPR-mean UPR atthat GA)/SD of UPR at that GA.Compare the Z-score in each group to the controlgroup.Results (1)Bland and Altman’s graphic plots confirm the significant agreementbetween intra-and inter-observer.The ICC of intra-and inter-observer were0.999and0.993,respectively.(2) UPR of digestive tube obstruction group,CNS defects groupand anencephalia group did not differ from that of the control group (Z-score were -0.20±0.31,0.05±1.980.12±0.85and-0.26±0.46,respectively, P＞0.05).Conclusions (1) Measuring of fetal bladder volumn using VOCAL technique bythree-dimensional ultrasonography has satisfactory accuracy and consistency, so thatcan be used to calculate fetal UPR.(2)Fetal UPR is normal in fetuses with digestivetube obstruction.The reason why the defect is usually complicated withpolyhydramnios is the reduction of absorption in the digestive tube.(3)No matter it isanencephalia or other types,fetal UPR in CNS defects is normal.It is not the increaseof urine production that causes polyhydramnios in CNS defects. Objective To evaluate the changes of fetal urine production rate (UPR) inhypertension disorders in pregnancy and intrautrine growth restriction (IUGR).Methods58women with normal singleton pregnancy at15～38weeks’ gestationwere selected as the control group.47consecutive cases with hypertension disordersin pregnancy and47consecutive cases with IUGR in the same period were selected asthe case group.According to the severity of hypertension disorders in pregnancy，the47cases were divided into3subgroups：13cases with gestational hypertension，14cases with mild preeclampsia and20cases with severe preeclampsia. Fetal bladdervolume was measured within a2～5minute interval using the virtual organcomputer-aided analysis(VOCAL) technique by three-dimensional ultrasonogaphy，and fetal UPR was calculated using the equation UPR (ml/h)=(the second bladdervolomn-the first bladder volomn)×60/time interval（min）.Measure the UPR in allgroups respectively.To adjust for gestational age (GA)，UPR was transformed toZ-score using the formulae： Z-score=(measured UPR-mean UPR at that GA)/SD ofUPR at that GA.Compare the Z-score of each group to the control group.Results (1) Fetal UPR of gestational hypertension was slightly lower than the controlgroup（Z-score were-0.43±0.30and-0.26±0.46,respectively），but there was nosignificant difference between the two groups（P＞0.05）. Fetal UPR of mild andsevere preeclampsia had significant differences when compared to the control group（Z-score were-0.65±0.20and-1.09±0.57,respetively,P＜0.01）. Moreover，fetalUPR of severe preeclampsia was significantly lower than mild preeclampsia（P＜0.05）.(2) Fetal UPR of fetuses with IUGR was significantly lower than the controlgroup（Z-score was-1.13±0.61,P＜0.001）.Conclusions (1)Changes of fetal UPR in hypertension disorders in pregnancy areassociated with the severity of the disease. Fetal UPR is normal in gestational hypertension，and decreased gradually in mild and severe preeclampsia.(2) Fetal UPRdecreased significantly in IUGR fetuses.