Assessment of umbilical cord coiling during the routine fetal sonographic anatomic survey in the second trimester.

OBJECTIVE: The purpose of this study was to evaluate the sonographic accuracy to determine the umbilical coiling index (UCI) during the routine fetal anatomic survey in the second trimester. METHODS: In 300 consecutive women with singleton pregnancies and absence of gross fetal anomalies who had a routine second-trimester fetal anatomic survey, a distance between 2 pairs of coils was measured from the longitudinal images of the umbilical cord, and the antenatal UCI (aUCI) was calculated. The aUCI was compared with true UCI results obtained after birth. RESULTS: Two hundred thirty-six patients had adequate sonographic umbilical cord images, and all required demographic, antenatal, and labor data collection to meet the inclusion criteria. A statistically significant correlation between aUCI and true UCI was found (P < .0001; r = 0.643). The mean aUCI was 0.402 (80% confidence interval, 0.382), and the true UCI at birth was 0.203 (80% confidence interval, 0.176). The sonographic evaluation showed 12.3% and 8.9% of hypocoiled and hypercoiled cords, whereas evaluation at birth found 10.6% and 8.1% hypocoiled and hypercoiled umbilical cords, respectively. The sensitivity values of sonography to predict hypocoiling and hypercoiling at birth were 78.9% and 25.4%, respectively. CONCLUSIONS: A sonographic evaluation of umbilical cord coiling in the second trimester correlates with the true UCI at birth, although the sensitivity in predicting coiling patterns as hypocoiled and hypercoiled cords is less accurate. A difference between the aUCI and matched UCI at birth could be explained by a sonographic error in the sampling of different umbilical cord segments with discordant coiling patterns or the possibility of a dynamically evolving UCI with advancing gestational age.     

Prenatal ultrasonographic prediction of the umbilical coiling index at birth and adverse pregnancy outcome.

OBJECTIVES: To evaluate whether the antenatal umbilical coiling index (aUCI) as measured by ultrasonography predicts the postnatal umbilical coiling index (pUCI) and adverse pregnancy outcome. METHODS: In a prospective study in 117 pregnancies, the aUCI was measured between 28 weeks and term by ultrasonography. The aUCI was calculated as the reciprocal value of the mean pitch of one complete coil. The pUCI was calculated as the number of coils divided by the cord length in cm. The correlation between aUCI and pUCI was assessed and likelihood ratios for adverse pregnancy outcome were calculated. RESULTS: We had complete data on 81 subjects. Mean aUCI +/- SD was 0.30 +/- 0.09 and mean pUCI +/- SD was 0.17 +/- 0.08. The correlation coefficient between aUCI and pUCI was 0.66, P < 0.001. Limits of agreement were 0-0.28 coils/cm. The positive likelihood ratio for small-for-gestational-age infants was 2.6 (95% confidence interval (CI) 0.6-11.6) for ultrasound hypocoiling, and 5.7 (95% CI 1.3-24.8) for ultrasound hypercoiling. The positive likelihood ratio for interventional delivery for non-reassuring fetal status was 1.2 (95% CI 0.2-9.0) for ultrasound hypocoiling, and 10.3 (95% CI 2.1-50.2) for ultrasound hypercoiling. CONCLUSIONS: Strong correlation coefficients comparing the aUCI and pUCI do not reflect agreement. Since the limits of agreement were almost as wide as the full range for the pUCI, the aUCI does not predict the pUCI with sufficient precision. Larger prospective studies are required to confirm the predictive potential of the aUCI for adverse pregnancy outcome.     

Antenatal umbilical coiling index and Doppler flow characteristics.

OBJECTIVE: To evaluate whether a relationship exists between the antenatal umbilical coiling index (UCI) and umbilical cord Doppler flow characteristics. METHODS: During the fetal anatomical survey in 200 consecutive pregnant patients at 18-23 weeks' gestation, we recorded umbilical coiling patterns and blood flow characteristics. The antenatal UCI, calculated as a reciprocal value of the distance between a pair of umbilical cord coils, was compared with Doppler parameters including umbilical vein blood flow volume (in mL/min/kg), and mean resistance index (RI) and peak systolic velocity (PSV in cm/s) averaged from both umbilical arteries. RESULTS: A total of 154 patients met the inclusion criteria of singleton pregnancy and having adequate sonographic umbilical cord images, Doppler flow indices, and all demographic, antenatal and labor data. The mean antenatal UCI was 0.40, with 10th and 90th centiles of 0.20 and 0.60, respectively. The mean +/- SD umbilical artery RI and PSV and umbilical vein blood flow volume were 0.74 +/- 0.07, 25.1 +/- 6.4 cm/s, and 264 +/- 106 mL/min/kg, respectively. All Doppler variables correlated significantly with antenatal UCI, with lower RI and higher PSV and umbilical vein blood flow volume values being associated with higher antenatal UCI (P = 0.016, P < 0.001, and P = 0.032, respectively). However, when stratified by antenatal UCI into hyper- (above 90th centile), normo- (10th-90th centile), and hypocoiled (below 10th centile) umbilical cord groups, a significant difference was observed for PSV only (P = 0.016). CONCLUSION: It appears that umbilical cord coiling modulates noticeably blood flow through the umbilical cord. We speculate that more prominent umbilical coiling (higher antenatal UCI values) has a protective effect on blood flow in terms of decreased arterial resistance and higher blood flow velocities, as well as increased venous blood flow. However, due to lack of significant differences between Doppler characteristics when stratified by antenatal UCI into hypo-, normo-, and hypercoiled groups, the clinical implications of this observation are uncertain.     

Umbilical vein blood flow in fetuses with normal and lean umbilical cord.

OBJECTIVE: To evaluate whether umbilical vascular coiling is correlated with the umbilical vein blood flow profile and to investigate if this is different between fetuses with a lean and those with a normal umbilical cord. METHODS: Consecutive women with a singleton gestation who delivered at term and who underwent an ultrasound examination within 24 h from delivery were studied. Umbilical cord and vessel areas were calculated. Umbilical vein blood flow parameters were obtained by digital color Doppler velocity profile integration. After delivery, the umbilical coiling index was calculated. RESULTS: One hundred and sixteen women were studied. Twelve (10.3%) had a lean umbilical cord (area < 10th centile). A significant correlation was found between the umbilical coiling index and the umbilical vein blood flow (r = 0.67, P < 0.001). A significant difference between fetuses with and without a lean cord was found in terms of: umbilical coiling index (0.18 +/- 0.08 vs. 0.29 +/- 0.09, P < 0.005), cord area (87.6 +/- 5.1 mm2 vs. 200.6 +/- 34.6 mm2, P < 0.001), Wharton's jelly amount (25.7 +/- 10.3 mm2 vs. 122.1 +/- 33.4 mm2, P < 0.001), umbilical vein blood flow (93.7 +/- 17.8 ml/kg per min vs. 126.0 +/- 23.4 ml/kg per min, P < 0.001), and umbilical vein blood flow mean velocity (6.6 +/- 2.7 cm/s vs. 9.0 +/- 3.6 cm/s, P < 0.05). The proportion of fetuses with an umbilical vein blood flow < 80 ml/kg per min was higher when the cord was lean than when it was normal (25% vs. 1.9%, P < 0.01). CONCLUSIONS: Lean umbilical cords differ from normal cords not only from a structural point of view but also in the umbilical vein blood flow characteristics. This could explain the increased incidence of intrapartum complications and fetal growth restriction among fetuses with a lean and/or hypocoiled cord.     

Early second-trimester low umbilical coiling index predicts small-for-gestational-age fetuses.

OBJECTIVE: To evaluate the role of the early second-trimester Doppler velocimetric studies of the umbilical coiling index and umbilical cord cross-sectional area as tests for the prediction of small-for-gestational age infants. METHODS: Doppler blood flow studies in 147 singleton pregnancies at risk for delivery of a small-for-gestational-age neonate were performed at 15 +/- 1 (SD) weeks' gestation from the uterine artery, umbilical artery, middle cerebral artery, inferior vena cava, and ductus venosus. Pulsatility index values were calculated for the arteries, and preload index values and systolic-atrial contraction ratios were calculated for the veins. The sonographic cross-sectional area of the umbilical cord was measured in a plane adjacent to the insertion into the fetal abdomen. The umbilical coiling index was calculated by using sonographic longitudinal views of cord vessels from several segments antenatally and by dividing the total number of helices by cord length (centimeters) postnatally. Small-for-gestational-age neonates were identified when the birth weight was below the 10th percentile for gestational age. RESULTS: Among 147 pregnancies studied, 124 fulfilled the study criteria. Thirty-nine of the neonates were small for gestational age at birth (31.5%). The mean +/- SD gestational age at delivery of the appropriate-for-gestational-age neonates was 39.7 +/- 1.28 weeks, and that of the small-for-gestational-age neonates was 36.4 +/- 2.9 weeks (range, 28-40 weeks). The best single predictor of a small-for-gestational-age infant was the coiling index, with sensitivity of 79%, specificity of 86%, a positive predictive value of 72%, and a negative predictive value of 90%. CONCLUSIONS: The umbilical coiling index measured in the second trimester is useful in predicting the birth of a small-for-gestational-age infant and may serve as a marker for subsequent growth restriction.     

Single and multiple umbilical cord cysts in early gestation: two different entities.

OBJECTIVE: To investigate the prevalence of single and multiple umbilical cord cysts in the first trimester and to assess whether there is a difference in the pregnancy outcome between them. METHODS: A targeted sonographic morphological and morphometric evaluation of the umbilical cord was performed in consecutive patients between 7 and 14 weeks of gestation. Crown-rump length and umbilical cord diameter were measured in all cases. Nuchal translucency thickness was measured between 11 and 14 weeks' gestation. In pregnancies at very early gestational ages (7-10 weeks) an additional scan was performed between 11 and 14 weeks. RESULTS: A total of 1159 patients was screened. The prevalence of umbilical cord cysts was 2.1% (24/1159). The cysts were single and multiple in 18 and six cases, respectively. The median (range) largest umbilical cord cyst diameter was no different between multiple and single umbilical cord cysts (3.8 (2.1-18) mm vs. 3.05 (2.0-7.8) mm; P = 0.386). All women with a single umbilical cord cyst delivered an infant without structural abnormalities and without features suggestive of chromosomal abnormalities. Among the women with multiple umbilical cord cysts, four had a missed miscarriage and one had a fetus with obstructive uropathy. CONCLUSION: Single and multiple umbilical cord cysts in the first trimester of gestation represent two different entities. While single cysts in the first trimester are associated with a favorable pregnancy outcome, the presence of multiple umbilical cord cysts is associated with an increased risk of miscarriage and aneuploidy.     

彩超评估脐带旋转指数与脐带异常附着的相关性研究

目的：观察脐带旋转指数异常与脐带附着异常是否相关。方法：超声检测350例孕晚期胎儿的脐带旋转指数（1／A）。该指数为脐动脉围绕脐静脉旋转1个周期后占脐静脉的长度的倒数,指数小于0．1考虑为少旋转。分娩后测量脐带附着点到胎盘边缘的距离,将结果分为正常附着、边缘性附着和帆状附着。结果：少旋转组的胎儿脐带约有76．5％为异常附着,正常旋转或高旋转约有2．2％的脐带异常附着,胎儿脐带旋转指数与脐带附着点到胎盘边缘距离之间的相关系数为r=0．953。结论：脐带少旋转与脐带异常附着有显著相关性,若存在脐带少旋转则可提示存在脐带异常附着。     

Frequency and nature of structural anomalies in fetuses with single umbilical arteries.

Published studies differ concerning the rate of anomalies occurring in the presence of a single umbilical artery and the significance of the single umbilical artery as an isolated sonographic finding. We assessed the frequency, nature, and sonographic detection of structural anomalies in fetuses with a single umbilical artery. We identified all cases in which prenatal sonography diagnosed a single umbilical artery. Cases were excluded if postnatal physical or pathologic examination demonstrated a three-vessel cord, yielding a study population of 167 cases. For each case, we recorded the gestational age at diagnosis of single umbilical artery and the findings of the sonographic fetal anatomic survey. We recorded postnatal clinical and pathologic information when available. Gestational age at time of diagnosis ranged from 16.8 to 41.1 weeks (mean, 29.2 +/- 6.5 weeks). Twenty of the 167 fetuses (12%) were twins, and the remainder were singletons. Among 118 cases with postnatal information, 37 (31%) had structural abnormalities, often involving multiple organs. The most common organ systems involved were the heart (19 cases) and the gastrointestinal (14 cases) and central nervous systems (nine cases). Five of the anomalous fetuses had abnormal karyotypes. The sonographic survey was abnormal in 31 of the 37 anomalous fetuses (84%). Among 85 cases with apparently isolated single umbilical artery at sonography and known fetal outcome, six (7%) proved to be anomalous at birth. We had two sonographic false-positive results (mild hydronephrosis, suspected skeletal dysplasia). In summary, approximately one third of fetuses with single umbilical artery have structural anomalies, most often cardiac. Even when the single umbilical artery is an apparently isolated sonographic finding, the likelihood that the neonate will prove to have structural anomalies is considerable (7% in our series).     

Large cross-sectional area of the umbilical cord as a predictor of fetal macrosomia.

OBJECTIVE: To determine whether a large cross-sectional area of the umbilical cord is a predictor of fetal macrosomia. METHODS: Consecutive patients of > 34 weeks' gestation, who presented for sonographic examination and who delivered within 4 weeks of the examination, were included in the study. The sonographic cross-sectional areas of the umbilical cord, the umbilical vessels and the Wharton's jelly were measured in a free loop of the umbilical cord. Logistic regression analysis was used to determine significant predictors of macrosomia (actual birth weight > 4000 g and > 4500 g). Fetal biometric parameters (biparietal diameter, abdominal circumference and femur length), sonographic estimated fetal weight and umbilical cord area > 95(th) centile for gestational age were used as covariates. RESULTS: During the study period, 1026 patients were enrolled. Fifty-three (5.2%) newborns had a birth weight > 4000 g, and 22 (2.1%) weighed > 4500 g. The proportion of cases with a large umbilical cord was significantly higher in the group of macrosomic compared with non-macrosomic infants (54.7% vs. 8.7%, P < 0.0001). Multiple regression models demonstrated an independent contribution of the large cord in the prediction of birth weight > 4000 g and > 4500 g (odds ratio (95% CI), 20.6 (9.2-45.9) and 4.2 (1.2-17.7), respectively). The sensitivity, specificity and positive and negative predictive values of a sonographic large umbilical cord were 54.7%, 91.3%, 25.4%, and 97.4%, respectively. The combination of abdominal circumference > 95(th) centile and large cord predicted 100% of macrosomic infants. The proportion of umbilical cords with a Wharton's jelly area > 95(th) centile for gestation was significantly higher in macrosomic fetuses of diabetic compared with non-diabetic mothers. CONCLUSIONS: Sonographic assessment of umbilical cord area may improve the prediction of fetal macrosomia.     

Fetal aneuploidy and umbilical cord thickness measured between 14 and 23 weeks' gestational age.

OBJECTIVE: To evaluate and compare umbilical cord thickness of aneuploid fetuses with umbilical cord diameter nomograms generated from euploid fetuses between 14 and 23 weeks' gestational age. METHODS: A retrospective study was conducted in which 56 fetuses and neonates had diagnoses of abnormal karyotypes, of which 46 fetuses had numerical chromosomal abnormalities. Among these cases, 26 subjects with adequate umbilical cord sonographic images were included in the study. The umbilical cord thickness was measured and plotted against the umbilical cord diameter nomogram that was generated from previously published data. RESULTS: From 26 evaluated fetuses and neonates, in 14 subjects (53.8%), the umbilical cord thickness was greater than the 95th percentile for gestational age. A thick umbilical cord was observed in 57.8% of fetuses with trisomy 21 and 50% of subjects with trisomy 18 and monosomy 45,XO. One fetus with trisomy 2 had umbilical cord thickness within the normal range. The largest number of aneuploid fetuses with thick umbilical cords (87.5%) was observed between 16 and 17 gestational weeks. CONCLUSION: Aneuploid fetuses have thicker umbilical cords than euploid fetuses. The umbilical cord thickness can be related to an increased amount of Wharton jelly. Because of the smaller number of thick umbilical cords in aneuploid subjects at later gestational ages, we speculate that abnormal cord thickness has a natural tendency toward its own resolution with the advancement of gestational age.     

Clinical significance of first trimester umbilical cord cysts.

A cystic mass of the umbilical cord was identified by transvaginal sonography in 10 first trimester pregnancies at a mean gestational age of 8 weeks 4 days (range, 8 weeks 1 day to 9 weeks 3 days) and at a mean crown-rump length of 20.5 mm (range, 15 to 25 mm). The cyst was solitary in all cases, the mean diameter was 4.6 mm (range, 3 to 6 mm), and the location was closer to the fetal insertion in two cases, in the middle of the cord in seven cases, and closer to the placental insertion in one case. Gestational sac and yolk sac diameters as well as the fetal heart rate were within normal ranges for gestational age in all cases. Information on detailed second trimester scans was available in nine cases, demonstrating complete resolution of the cyst and normal fetal anatomic survey in each case. These nine pregnancies were followed to delivery, and normal healthy infants were delivered at term in all cases. This series suggests that the incidental detection of umbilical cord cysts in early pregnancy is not associated with an adverse pregnancy outcome.     

First-trimester umbilical cord diameter: a novel marker of fetal aneuploidy.

OBJECTIVE: To compare the umbilical cord diameter at 10-14 weeks of gestation of chromosomally normal and abnormal fetuses. METHODS: In a consecutive series of women, who were undergoing routine sonographic evaluation at 10-14 weeks of gestation, umbilical cord diameter and nuchal translucency were measured. Reference ranges for umbilical cord diameter according to gestational age and crown-rump length were constructed. Fetal karyotype was obtained at chorionic villus sampling, amniocentesis or at delivery in newborns with features suspicious for chromosomal abnormalities. RESULTS: During the study period, 784 patients met the inclusion criteria. Of these, a fetal or placental chromosomal abnormality was present in 17 cases. The mean umbilical cord diameter increased with gestational age (r = 0.41, P < 0.001).The proportion of fetuses with an umbilical cord diameter above the 95th centile was higher in the presence of fetal or placental chromosomal abnormalities than in normal fetuses (5/17 vs. 39/767, P < 0.01). Among fetuses with an abnormal fetal or placental karyotype, nuchal translucency was above the 95th centile for gestational age in 10 cases.When only fetal chromosomal abnormalities were considered (n = 14), the combined detection rate was 85.7%(12/14). CONCLUSIONS: Sonographic assessment of the umbilical cord in early gestation appears to identify a subset of fetuses at increased risk of chromosomal abnormalities.     

First-trimester sonographic umbilical cord diameter and the growth of the human embryo.

OBJECTIVES: Experimental and clinical evidence have shown that the morphometry of the umbilical cord in the second half of gestation might be useful in predicting adverse perinatal outcome. The purposes of this study were to generate a nomogram for the umbilical cord diameter in the first trimester and, in an observational study, to investigate whether the sonographic measurement of the umbilical cord diameter early in gestation has the same clinical value as that late in gestation. METHODS: The sonographic umbilical cord diameter, crown-rump length and biparietal diameter were measured in 439 fetuses at between 8 and 15 weeks of gestation. The perinatal outcome was recorded for all patients. RESULTS: The umbilical cord diameter increased steadily from 8 to 15 weeks of gestation. A significant correlation was found between umbilical cord diameter and gestational age (r = 0.78; P < 0.001), umbilical cord diameter and crown-rump length (r = 0.75; P < 0.001) and umbilical cord diameter and biparietal diameter (r = 0.81; P < 0.001). No correlation was found between umbilical cord diameter values and either birth weight or placental weight. Among patients who had a miscarriage (n = 7) and pre-eclampsia (n = 8) the umbilical cord diameter was below 2 standard deviations from the mean in three cases (42.9%) and three cases (37.5%), respectively. CONCLUSION: The measurement of the umbilical cord diameter in the first trimester is correlated with the growth of the embryo and may be a marker for identifying a subset of fetuses at risk of spontaneous miscarriage and pre-eclampsia.     

Second-trimester ultrasonographic assessment of the umbilical coiling index.

OBJECTIVE: To determine the relationship between gestational age and the ultrasonic measurement of umbilical coiling index (UCI), and to assess the ability of second-trimester ultrasonic measurements of UCI to predict the true UCI, determined at birth. SUBJECTS/METHODS: Five hundred and thirty-one consecutive women with uncomplicated pregnancies, booking for delivery with a singleton pregnancy, were recruited during a routine second-trimester fetal morphology scan. Multiple ultrasonographic measurements of the intercoil distance were performed between two to three coils of the umbilical cord, along its entire visible length. Three hundred and seventy-four patients (70%) were followed until delivery when the true UCI was measured. RESULTS: An adequate portion of umbilical cord for assessment of coiling was visualized in 99% of cases. Adequate ultrasonographic visibility rates for the fetal, middle and placental regions of the cord were different. All three regions of the umbilical cord could only be visualized adequately in 10% of cases, and two regions were visible in 75%. The UCI progressively decreased along the cord from the fetal insertion to the placental insertion. The mean decrease in UCI with increasing gestational age was similar in all parts of the cord before the 23rd week (160 days) of pregnancy, and plateaued off after this point, except in measurements performed near the fetal insertion. The sensitivity of second-trimester ultrasound examination for predicting hypercoiling at birth was 17.3% and for predicting hypocoiling was 9.1%. DISCUSSION: Whilst UCI can be measured easily and reliably in the second trimester these estimates do not accurately reflect the UCI at term. Our original assumption that umbilical coiling does not alter after the initial formation of coils in the first trimester is incorrect; mixed patterns occurred in about 25% of cases. These patterns develop during the second and third trimesters, presumably due to snarls in the cord, and influence the final coiling number and therefore the relationship between the two measurements of UCI.     

Sonography of normal fetal bowel

This is a prospective study of the sonographic appearance of normal small bowel and colon in 300 fetuses. Normal fetal bowel can be frequently seen during sonographic examination. The diameter of the lumen of the small bowel and colon increases as gestational age increases. The fetal small bowel lumen rarely exceeds 6 mm in diameter, and fetal colon lumen diameter rarely exceeds 23 mm. Small bowel peristalsis can be seen with increasing frequency with increasing gestational age. Colon peristalsis is not seen. Haustral folds in the colon can be frequently demonstrated. Meconium in the colon always remains hypoechoic relative to the fetal liver and bowel wall. Hyperechoic appearance of the small bowel in early gestation and cystic appearance of parts of the colon in later gestation may mimic pathology. Normal herniation of bowel into umbilical cord can be seen in early (8 to 11 weeks) gestation.     

Nomogram of Wharton's jelly as depicted in the sonographic cross section of the umbilical cord.

OBJECTIVES: To generate a nomogram for the sonographic measurement of Wharton's jelly area (WJA) during gestation and to investigate whether WJA is related to fetal biometric parameters. METHOD: The sonographic cross-sectional area of the umbilical cord and of its vessels was measured in 659 fetuses between 15 and 42 weeks of gestation. The WJA was calculated by subtracting the vascular area from the umbilical cord area. The conventional biometric parameters were measured and correlated with the WJA. Polynomial regression analysis was utilized for statistical purposes. RESULTS: The WJA increased as a function of gestational age (r = 0.63, P < 0.001). The regression equation for the mean WJA (y) according to gestational age (x) was y = -114.7 + 4.142x - 0.01x2 and for the standard deviation (y') was y' = -7.567 + 1.319x. There was a strong correlation between the WJA and the umbilical cord area (r = 0.97, P < 0.001). A significant correlation was also found between the WJA and fetal biometric parameters before 32 weeks of gestation (WJA and biparietal diameter: r = 0.82, P < 0.001; WJA and abdominal circumference: r = 0.79, P < 0.001; WJA and femur length: r = 0.81, P < 0.001) while after 32 weeks of gestation no correlations were found between WJA and fetal anthropometric parameters. CONCLUSION: A nomogram for the WJA has been generated. The WJA increases as a function of gestational age and it is correlated with fetal size up to 32 weeks of gestation.     

Prenatal color Doppler sonographic evaluation of nuchal encirclement by the umbilical cord

PURPOSE: The aim of this study was to assess whether Doppler flow velocimetry of the fetal middle cerebral and umbilical arteries is affected by nuchal encirclement by the umbilical cord (nuchal cord) in the prenatal period. PATIENTS AND METHODS: The position of the fetal umbilical cord was assessed on color Doppler sonography in pregnant women who were referred to our radiology department between September 14, 1998, and January 14, 2000. Pulsatility and resistance indices and the ratio of peak systolic blood flow velocity to diastolic velocity of the umbilical arteries and middle cerebral arteries of all fetuses were prospectively obtained with Doppler flow velocimetry. The fetuses were categorized into 2 groups: group 1 consisted of fetuses without sonographic evidence of nuchal cord and group 2 of fetuses with sonographic evidence of nuchal cord. The results were statistically analyzed with independent-groups t test. A p value of less than 0.05 was considered significant. RESULTS: During the study period, 230 pregnant women underwent sonographic examination of the fetus, and 68 fetuses were delivered. The sonographic examinations were performed at 24-41 weeks' menstrual age. Of the 46 fetuses in group 1, 1 fetus had nuchal cord at delivery; of the 22 fetuses in group 2, 4 did not have nuchal cord at delivery. The sensitivity of color Doppler sonography in detecting nuchal cord was 95% (18 of 19 fetuses), the specificity was 92% (45 of 49), the negative predictive value was 98% (45 of 46), and the positive predictive value was 82% (18 of 22). No statistically significant differences in middle cerebral artery or umbilical artery Doppler flow velocimetry values were detected between the 2 groups. CONCLUSIONS: Color Doppler sonography is a sensitive and specific method of diagnosing nuchal cord, but fetal middle cerebral artery and umbilical artery Doppler flow velocimetry values are not affected by the presence of nuchal cord in the prenatal period.     

First-trimester diagnosis of body stalk anomaly using 2- and 3-dimensional sonography

To determine the sonographic features of body stalk anomaly in the first trimester using 2-dimensional (2D) and 3-dimensional (3D) sonography, we conducted a retrospective analysis of all nuchal translucency sonographic examinations performed between January 1, 2006, and January 1, 2010, at our institution. From a total of 6952 nuchal translucency sonographic examinations, 4 cases of body stalk anomaly were identified. All cases were characterized by an absent umbilical cord and a large ventral wall defect with herniation of the abdominal contents into the extraembryonic coelom. Associated features included kyphoscoliosis, limb defects, and enlarged nuchal translucency measurements. Three-dimensional sonography was a useful adjunct to 2D techniques in determining the precise relationship of fetal structures to the amniotic cavity. Our case series emphasizes the importance of a thorough anatomic survey at the time of nuchal translucency screening and the value of 3D sonography in the delineation of first-trimester anomalies.     

Umbilical cord cyst detected in the first trimester by two- and three-dimensional sonography

A case of umbilical cord cyst was identified via 2-dimensional and 3-dimensional sonographic examination at 8 weeks' menstrual age. The cyst was solitary, measuring 18.0 mm, and it was located close to the placental insertion on the umbilical cord. The gestational sac and yolk sac diameters and the fetal heart rate were within normal ranges for menstrual age. Follow-up 3-Dimensional sonographic examination in the second trimester showed complete resolution of the cyst. Amniocentesis revealed a normal karyotype, and a normal infant was delivered at term.     

Fetuses with trisomy 21 having conflicting findings on antenatal testing for fetal well-being.

OBJECTIVE: This series reports 3 cases with conflicting antenatal sonographic findings: intrauterine growth restriction, absent or reversed end-diastolic flow in umbilical artery Doppler imaging, and reassuring biophysical test results. METHODS: We conducted a retrospective review of medical records. RESULTS: Three fetuses had intrauterine growth restriction and absent or reversed end-diastolic flow in umbilical artery Doppler studies, but the biophysical test results and amniotic fluid volume assessment were normal. We found no other signs of fetal jeopardy from placental insufficiency. In these cases, trisomy 21 was established after birth by karyotyping. Ventricular septal defects and aortic regurgitation were noted in 2 of the 3 affected fetuses. CONCLUSIONS: When there is an unusual combination of antenatal sonographic findings such as presented here, fetal cardiac abnormalities and aneuploidy should be considered.