Prenatal detection of velamentous insertion of the umbilical cord: a prospective color Doppler ultrasound study.

OBJECTIVE: Velamentous insertion of the umbilical cord, with a reported incidence of 1% in singleton pregnancies, has been associated with several obstetric complications including fetal growth restriction, prematurity, congenital anomalies, low Apgar scores, fetal bleeding and retained placenta. The aim of this study was to determine the feasibility of identifying velamentous insertion of the umbilical cord during routine obstetric ultrasound. DESIGN: This was a prospective, cross-sectional ultrasound study in 832 unselected second- and third-trimester singleton pregnancies. Color Doppler ultrasound was routinely performed to identify the placental cord insertion site. The role of three-dimensional (3D) ultrasound in evaluating the placental cord insertion site was also studied in a subset of 50 pregnancies from this population. RESULTS: The placental cord insertion site was identified in 825/832 (99%) cases. Visualization was not achieved in seven third-trimester pregnancies with a posterior placenta. A velamentous insertion was suspected prenatally in eight cases, seven of which were confirmed after delivery as velamentous and one as markedly eccentric (battledore placenta). 3D ultrasound performed poorly at evaluating placental cord insertion site, being less efficient due to poor-quality resolution and far more time-consuming than the combined use of gray-scale and color Doppler ultrasound. CONCLUSIONS: Velamentous insertion of the umbilical cord can reliably be detected prenatally by gray-scale and color Doppler ultrasound. 3D imaging had limited value in the evaluation of the placental cord insertion site in our subset of patients. Systematic assessment of the placental cord insertion site at routine obstetric ultrasound has the potential of identifying pregnancies with velamentous insertion and, therefore, those at risk for obstetric complications including vasa previa.

Risks of funipuncture in fetuses with single umbilical arteries.

OBJECTIVE: To estimate procedure-related risks of funipuncture in fetuses with single umbilical arteries (UAs). METHODS: We identified fetuses that had blood samples collected by funipuncture and in which single UAs were detected, prenatally or postnatally. We also recorded maternal demographics, prenatal sonographic findings, gestational age at the time of the procedure, procedure-related complications, and perinatal outcomes. RESULTS: Over 2 years, 14 fetuses identified as having single UAs had funipuncture for prenatal karyotyping at a median gestational age of 29 weeks (range 20-34 weeks). Each had additional abnormal prenatal sonographic findings. The approach to the cord was transplacental in six cases and transamniotic in eight. There were no failed procedures, and 13 of 14 funipunctures were successful on the first attempt. Three fetuses (21%) had complications (bradycardia in two cases and bleeding in one case), a complication rate not greater than that reported in large series of fetuses that had fetal blood sampling. All three complications were associated with the transamniotic approach. There were no procedure-related pregnancy losses within 2 weeks of the procedure in this series. CONCLUSION: Funipuncture does not seem to be associated with increased risk of procedure-related complications or pregnancy losses in fetuses with single UAs, although the risk could be greater with transamniotic than with transplacental sampling.

Pseudocyst of the umbilical cord: prenatal sonographic appearance and clinical significance.

OBJECTIVE: To assess the clinical significance of umbilical cord pseudocysts detected prenatally by sonography. METHODS: The prenatal sonographic findings, karyotype, and perinatal outcome in 13 fetuses with umbilical cord pseudocysts were reviewed retrospectively. RESULTS: Umbilical cord pseudocysts were diagnosed at a median gestation of 27 weeks (range 15-37). Pseudocysts were single in eight cases with cyst diameters ranging from 20 to 50 mm, and double in one case. In the remaining four cases, multiple small cystic masses measuring less than 8 mm were identified. Additional sonographic findings were noted in 11 cases; ten of these fetuses had prenatal karyotyping, which showed trisomy 18 in five cases, trisomy 13 in one case, and a 46,XX, inv ins(18;21) complement in one case. Among the seven chromosomally abnormal fetuses, umbilical cord pseudocysts were multiple in four fetuses and single in three. All chromosomally abnormal fetuses and two euploid fetuses with associated structural defects died in utero or in the neonatal period. There were no perinatal complications in either of the fetuses with isolated pseudocysts. CONCLUSION: The prenatal sonographic appearance of umbilical cord pseudocysts varied widely. These umbilical cord cystic masses were associated strongly with chromosomal disorders and structural defects, regardless of their sonographic appearance in utero.

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.

Sirenomelia sequence versus renal agenesis: prenatal differentiation with power Doppler ultrasound.

In order to assess the role of power Doppler ultrasound in the prenatal diagnosis of sirenomelia, prenatal findings in two fetuses with the sirenomelia sequence and in seven with bilateral renal agenesis were reviewed and compared. Both conditions were characterized by absence of renal vessels. However, the two common iliac arteries were always visualized in fetuses with renal agenesis, whereas absence of distal branching of the main abdominal vessel was a characteristic feature of sirenomelia. Power Doppler ultrasound allows expeditious identification of absent or non-functional renal arteries in fetuses with severe oligohydramnios. In addition, incorporation of power Doppler imaging to identify the aortic bifurcation could provide a diagnostic feature that could assist in the prenatal diagnosis of sirenomelia and in the differential diagnosis with other causes of bilateral renal agenesis.

[Severe fetal hemolytic disease. Evaluation and successful treatment by means of cordocentesis]. / Enfermedad hemolítica fetal severa. Evaluación y tratamiento exitoso mediante cordocéntesis.

Ultrasonically guided access to the fetal umbilical circulation offers an alternative to the standard management of the severe isoimmunized pregnancy. This technique allows fetal blood sampling, direct hematocrit analysis and intravascular transfusion. A severely Rh isoimmunized pregnancy is described in which five intrauterine transfusions of blood were given directly into the umbilical vein under ultrasound visualization. Technical aspects of the procedure and complications are discussed.