17th World Congress on Ultrasound in Obstetrics and Gynecology Poster abstracts because of contractions was performed at 32/6 weeks of gestation. A viable 1840 g female infant with Apgar scores of 8, 8 and 9 and umbilical artery pH 7.32 was delivered. At the time of delivery, approximately 600 mL of fresh blood gushed from the uterine incision before amniotomy. The total estimated blood loss from the surgery was 500 mL. The mother had an unremarkable postoperative course and was discharged in stable condition on postpartum day 8. The neoanate was admitted to the neonatal intensive care unit for prematurity and respiratory distress syndrome. P27.12 Three-dimensional sonographic evaluation estimation of maternal hydronephrosis volume and its association with urinary tract infection S. Wozniak , P. Szkodziak, E. Wozniakowska, M. Paszkowski, T. Pszkowski Medical University of Lublin, Poland Introduction: In the clinical evaluation of pregnant women no data exists about the use of three-dimensional (3D) ultrasound for imaging the maternal kidney to demonstrate an accuracy of 3D volume assessment of association hydronephrosis volume (HV) and urinary tract infection (UTI). Bacteriuria > 105 CFU/mL is the evidence of UTI even in the absence of associated signs and symptoms. The consequences of UTI during pregnancy can be significant, including an elevated risk of pyelonephritis, premature delivery and fetal mortality. Objectives: The aim of the study was to evaluate the accuracy of 3D ultrasound in the assessment of association between HV and UTI in pregnant women. Materials and methods: The study population consisted of 48 pregnant women with hydronephrosis. For each patients renal ultrasonography and urine culture were done. A three-dimensional volume of hydronephrosis in the transverse plane was performed using the VOCAL mode (Medison 9900). Results: An asymptomatic bacteriuria was found in 47.9% pregnant women with hydronephrosis. Urine culture was positive in 81.2% of patients. Bacteriuria ≥ 10 5 CFU/mL was found in 35.4% patients with hydronephrosis. The mean hydronephrosis volume in pregnant women with bacteriuria ≥ 10 5 CFU/mL was significantly (Mann-Whitney test U = 59.50; P < 0.001) greater then in patients with bacteriuria ≥ 10 5 CFU/mL (median 24.48 mL, 95% CI, 20.59–33.20 versus median 10.69 mL, 95% CI, 8.77–16.79). The hydronephrosis volume under 20 ml was found in 81.2% patients with bacteriuria ≥ 10 5 and only in 9.3% with bacteriuria < 10 5 . There was a linear positive correlation between HV and the bacteriuria grade (Rs = 0.5207; P < 0.001). Conclusions: Our study show that HV in pregnant women as measured by means of 3D ultrasonography constitutes a promising diagnostic tool. Screening for HV during pregnancy seems to be important in preventing the progression of asymptomatic bacteriuria to symptomatic urinary tract infection. P27.13 Changing of kidney volume in pregnancy-associated hypertension and/or proteinuria (3D study) A. Sur ´ anyi 1 , A. Kereszt ´ uri 1 , T. Ny ´ ari 2 , K. L ´ at ´ o 1 , A. P ´ al 1 1 Department of Obstetrics and Gynaecology of Szeged University, Hungary, 2 Department of Medical Informatics of Szeged University, Hungary Background: Very important investigation the urogenital tract screening during the pregnancy. The pathological kidney parameters refers to pathological renal function and development. Screened pregnancies were chronically hypoxic (i.e. pregnancy-associated hypertension and/or proteinuria). Materials and methods: The object of this study was to investigate the fetal kidney volume in normal and hyperechogenic kidneys during the third trimester of gestation. Depending on the renal manifestation of the intrauterine chronic hypoxia, the cases were broken downs into two study groups. Group I was composed of fetuses with pregnancy-associated hypertension and/or proteinuria and hyperechogenic renal medullae. Group II consisted of fetuses with pregnancy-associated hypertension and/or proteinuria and normal echoic kidney. Both study groups included pregnant women from the third trimester. Results: Fetal renal hyperechogenicity is an indicator of fetal renal perfusion depression, correlated with pathological growth in the fetal kidney development. The fetal kidney volume was significantly higher in hyperechogenic cases, than in the normal range. This may also be an in utero indication of subsequent intrauterine and neonatal complications. Conclusions: Detailed ultrasound examinations of renal parenchyma and volume appears to be an useful method in the prenatal diagnosis of reduced renal perfusion and of intrauterine hypoxia so as to detect possible pathological fetal conditions in utero. P27.14 Fetal cystic hygroma and mid-trimester maternal serum screening M. Liberati 1 , C. Celentano 1 , F. Prefumo 2 , I. Iezzi 3 , P. E. Guanciali-Franchi 3 , A. Iannicco 1 , E. Di Vera 1 , S. Rotmensch 4 1 Department of Obstetrics and Gynecology, Chieti University, Italy, 2 Department of Obstetrics and Gynecology, Brescia University, Italy, 3 Department of Genetics, Chieti University, Italy, 4 Department of Obstetrics and Gynecology, Wolfson Medical Center, Tel Aviv, Israel Fetuses affected by cystic hygroma have an increased risk for aneuploidy, mainly Turner syndrome but also Down syndrome, trisomy 18, triploidy, and sex chromosome aneuploidy; furthermore those fetuses have an increased incidence of hydrops, associated malformations and intrauterine death, being overall at high risk for adverse outcome. Cystic hygroma, however, may spontaneously resolve and euploid non-malformed fetuses may have a good outcome. Second trimester maternal serum screening is commonly used as a screening test for Down syndrome and trisomy 18, however, little is known about the relationship between cystic hygroma and maternal serum screening markers. We retrospectively reviewed case notes of 37 consecutive singleton fetuses with cystic hygroma referred at 15–18 weeks of gestation; in all cases maternal blood was sampled for triple screening at the time of the ultrasound scan. An abnormal karyotype was present in 59% of fetuses with cystic hygroma, and, overall, 81% of fetuses had a poor outcome. Of the 15 fetuses with euploid karyotype, six had altered and nine had normal maternal serum screen. All of the first six cases had a poor obstetric outcome, with four cases of associated anomalies; of the nine cases with normal maternal screen, five cases with normal karyotype, normal triple screen and absence of associated anomalies had a normal pregnancy outcome, three cases had a poor outcome and one fetus had no associated anomalies, normal triple screen, a 47,XYY karyotype a good outcome. Those preliminary results confirm that cystic hygroma at 15–18 weeks is strongly associated with chromosomal abnormalities and that in euploid fetuses with cystic hygroma, maternal serum screening results may play a role in the evaluation of the obstetrical risk. P27.15 Unusual prenatal presentation of twin reversed arterial perfusion sequence: ‘acardiac’ with a heart J. L. B. Byrne , H. Carney, J. C. Carey, A. Kennedy University of Utah, United States A first trimester scan showed monochorionic diamniotic (MCDA) twins with normal heart rates. One twin had a cystic hygroma and 556 Ultrasound in Obstetrics & Gynecology 2007; 30: 547–653