The measurement of cervical length utilizing transvaginal ultrasound is of help for pregnant women screening for premature labor, the shortening of the cervix being a predictor of higher risk of preterm delivery. Traditional methods for evaluating the uterine cervix during pregnancy are limited and unsatisfactory. Digital examination of cervix, considered as the standard method, demonstrates large variation among different examiners; on the other hand, transvaginal sonography is an effective method of examination during pregnancy. Recently, three-dimensional ultrasound has been used in the clinical practice including the study of uterine cervix. The three-dimensional technology allows acquisition and storage of a large volume of data. Such stored information can be reformatted and analyzed through an unlimited number of planes. The three-dimensional transvaginal ultrasound is the unique imaging method capable of obtaining a true coronal plane by direct correlation of the views in a multiplanar display. This method seems to offer a diagnostic potential because of the cervical ultrasonography increased accuracy.

Keywords: Uterine cervix, Pregnancy, Three-dimensional ultrasonography

OBJECTIVE: To assess the behavior of nuchal translucency (NT) in the population of the State of Espírito Santo, Brazil, during weeks 10 to 14 of pregnancy and to establish a reference range for this population. MATERIALS AND METHODS: A transversal study was performed in 853 fetuses which presented normal cariotype or phenotype. All the fetuses were submitted to ultrasound analysis for NT measurement, during routine ultrasound examinations. The Student's "t" test and ANOVA were used in the statistical analysis. The regression test was used to adjust the better mathematical model to translate the NT behavior. RESULTS: Maternal age varied between 14 to 49 years (mean 30.2%), and 22.1% were above 35 years of age. The NT measurement increased with gestational age and the crown-rump length (CRL). In 73 normal fetuses (6.46%) the NT was thicker than 2.5 mm. The better mathematical model was the linear correlation (NT = 0.414 + 0.020 × CRL) which allowed to establish the reference range (percentiles 5, 10, 25, 50, 75, 90 and 95). CONCLUSION: The NT measurement is a manageable method during the usual ultrasonography. NT measurements increase with gestational age during weeks 10 to 14 of pregnancy. The NT measurements seen in the population of the State of Espírito Santo were similar to other population tested.

Keywords: Nuchal translucency, Reference curve, Prenatal diagnosis

OBJECTIVE: To develop a nomogram for the umbilical cord cross-sectional area (UCCSA) in normal pregnancies in women between 20 to 40 weeks gestation. MATERIALS AND METHODS: A cross-sectional study was developed to determine reference ranges for the UCCSA during normal pregnancies (patients with known dates of last menstrual period, and a normal ultrasound examination before the 20th week of gestation). The measurements of the UCCSA were obtained using a plane adjacent to the insertion of the cord in the abdomen. A 3.5 MHz transabdominal transducer was used on all ultrasound equipment utilized (a Synergy Multi Sync M500, a Toshiba 140 and a Toshiba Corevision). The statistical analysis was performed using the SPSS (Statistical Package for Social Sciences) software. RESULTS: The Kolmogorov-Smirnov test showed a normal distribution of the data and the nomogram was constructed by linear regression. The analysis of variance (F test = 356.27) showed that our model was significant at a p < 0.01 level, and therefore represented adequately the studied population. The confidence interval (95%) contained the real value of the UCCSA. The equation constructed for the UCCSA (y) according to the gestational age (x) was: y = -532.27 + 44.358x - 0,655x². CONCLUSION: The nomogram developed for the UCCSA shows a progressive increase of the UCCSA up to the 32nd week, stabilization until the 34th week, and decrease after the 35th week of gestation.

Keywords: Umbilical cord, Cross-sectional area, Fetal growth

OBJECTIVE: To test the hypothesis that the application of ductus venosus Doppler velocimetry between 10--14 weeks gestation may serve as a screening tool for the detection of fetuses with Down syndrome and estimate a new criteria of risk. PATIENTS AND METHODS: 491 fetuses were studied consecutively. In 132 cases a cytogenetic study was performed on material obtained from a biopsy of the chorionic villus, and in 359 cases the postnatal phenotype was used as a basis for the result. In addition to the routine ultrasonographic examination, all the fetuses were submitted to measurement of the nuchal translucency thickness. T "student" and ANOVA tests were used for the statistical analysis. The sensitivity, specificity, positive and negative predictive values, true-positive probability and likelihood ratio were calculated. RESULTS: There were 21 cases of Down syndrome. On these 21 fetuses the ductus venosus blood flow during atrial contraction was either absent (n = 3) or reversed (n = 17) - sensitivity = 95.2%. In the chromosomally normal fetuses (n = 470) only 8 had abnormal Doppler findings in the ductus venosus (specificity = 98.2%, positive and negative predictive values = 71.4% and 99.8%, respectively, and positive and negative likelihood ratio = 56 and 0.1, respectively). CONCLUSION: Our preliminary results suggest that the presence of Down syndrome may be strongly suspected when there is reverse or absent flow in the ductus venosus Doppler velocimetry during atrial contraction. We speculate the possibility of a new criteria to calculate the new risk of Down syndrome based on Doppler examination of the ductus venosus. Using the program of the Fetal Medicine Foundation to assess the baseline risk, a multiplying factor of approximately 0.1 (negative predictive value) is applied for normal ductus whereas a multiplying factor of 50 is applied in case of reverse or absent ductus, thus establishing a new adjusted risk factor.

Keywords: Doppler velocimetry, Ductus venosus, Down syndrome, Prenatal diagnosis

The authors review the Doppler imaging methods and their evolution for the study of the fetal circulation emphasizing safety and bioeffects. Ultrasound machines work with thermal and mechanical indexes that are automatically kept under 1.0. Up to date, there have been no reports on biological lesions in human fetuses caused by diagnostic Doppler. Consequently, color, pulsed and power Doppler sonography are considered safe in prenatal exposure.

Keywords: Doppler velocimetry, Safety, Bioeffects, Prenatal

The advent of high-resolution transvaginal ultrasound scanning introduced new research possibilities for patients with polycystic ovaries. The knowledge of the ovarian hemodynamics is a prerequisite for understanding the pathophysiological behaviour of polycystic ovaries. The authors consider the possibility of using color Doppler for a better definition of polycystic ovaries. The findings suggest that increased stromal blood vessels with low resistance and increased pulsatility index of the uterine arteries are to be new parameters to assist in the ultrasound diagnosis of polycystic ovary syndrome. This is a preliminary conclusion and further investigations are necessary to confirm this proposition.

Keywords: Polycystic ovary, Ultrasonography, Color Doppler, Blood flow

We report a case of prenatal diagnosis of trisomy 9 in a fetus presenting increased translucency thickness (9.1 mm) observed on an ultrasound scan performed at 12 weeks pregnancy and confirmed by cariotype analysis of biopsy material obtained from the chorionic villi. Multiple trisomy 9 characteristic abnormalities were detected by ultrasound and confirmed by autopsy and histopathological examination. Although rare, trisomy 9 should be included in the list of chromosomic anomalies associated with increased translucency.

Keywords: Trisomy 9, Pathology, Prenatal ultrasound, Nuchal translucency, Chromosomal abnormalities