Sonographic umbilical cord morphometry and coiling patterns in twin-twin transfusion syndrome.

OBJECTIVE: Monochorionic twins with twin-twin transfusion syndrome (TTTS) provide an ideal model in which to evaluate the influence of differing hemodynamic stress on umbilical cord (UC) morphology. The purpose of this study was to investigate the UC morphometry and UC coiling pattern at ultrasound in monochorionic twin pregnancies with TTTS. METHODS: A targeted sonographic evaluation of the UC was performed in 21 consecutive twin pregnancies with untreated TTTS. The cross-sectional area of the UC and of its vessels was measured. The Wharton's jelly area was computed by subtracting the vessels area from the area of the UC. The umbilical coiling index (UCI) was calculated as the reciprocal of the sonographic length of one complete vascular coil. The UCs were classified as uncoiled, normally coiled, hypocoiled, hypercoiled and atypically coiled (UCI not valuable). RESULTS: The UCs of recipient twins were invariably larger than those of donors, and this difference was mainly attributable to both a larger amount of Wharton's jelly and a larger umbilical vein diameter. The proportion of lean UCs was higher in the donor than in the recipient fetuses (18/21 vs 1/21, p < 0.0001), while large UCs were significantly more frequent in the recipient than in the donor twins (13/21 vs 1/21, p = 0.0002). In all twin pairs, a discordant umbilical coiling pattern was observed between the donor and the recipient twin. The prevalence of uncoiled and hypocoiled cords was higher in the donor group, while hypercoiling and atypical coiling were more frequently detected in the recipient group. CONCLUSIONS: A discordant UC morphometry represents an additional phenotypic feature of twins with TTTS. The discordant intertwin coiling pattern in TTTS argues against an exclusively genetic origin of UC twists, and further supports a key role of hemodynamic forces in coiling development.

Sonographic umbilical vessel morphometry and perinatal outcome of fetuses with a lean umbilical cord.

PURPOSE: This study was undertaken to assess whether changes in umbilical cord vessel morphometry are associated with an increased risk of adverse perinatal outcome among fetuses with a lean umbilical cord on sonography. PATIENTS AND METHODS: A total of 160 fetuses with a sonographically lean umbilical cord (cross-sectional area below the 10th percentile for gestational age) after 20 weeks of gestation were enrolled. The cross-sectional areas of the umbilical cord and its vessels were measured. Outcome variables investigated were perinatal death, admission to the neonatal intensive care unit, intrauterine growth restriction, and 5-minute Apgar score. RESULTS: The proportions of perinatal death (1/96 versus 6/64, p < 0.05) and admission to the neonatal intensive care unit (17/96 versus 22/64, p < 0.05) was significantly higher among fetuses with an umbilical vein area below or equal to the 10th percentile for gestational age than among those with an umbilical vein area greater than the 10th percentile. No differences were found in the proportions of perinatal death, neonatal intensive care unit admission, 5-minute Apgar score < 7, and intrauterine growth restriction when fetuses with umbilical vein areas below or equal to the 10th, the 5th, and the 2.5th percentiles for gestational age were compared. No difference was found in the umbilical artery area and Wharton's jelly area among the groups. CONCLUSION: Among fetuses with a sonographically lean umbilical cord, a significant relationship exists between an umbilical vein area below or equal to the 10th percentile and an adverse neonatal outcome.

The thick heterogeneous (jellylike) placenta: a strong predictor of adverse pregnancy outcome.

OBJECTIVE: To present a series of cases with a sonographic thick and heterogeneous placenta, and to review the literature. METHODS: A series of 16 cases were analyzed. A heterogeneous placenta was defined as a thick placenta with a patchy decrease of echogenicity, which quivered like jelly to sharp abdominal pressure. A comprehensive morphologic and Doppler evaluation of the fetus and the uteroplacental circulation was performed. The pregnancy course and the neonatal outcome of the present series and of those reported in the literature were reviewed. RESULTS: Placental thickness was greater than the 95th centile in all cases. The placenta was located laterally in 13 (81.3%) cases. Twelve women delivered earlier than 34 weeks either spontaneously or because of deteriorating maternal and/or fetal conditions (n = 10). Perinatal death occurred in eight cases. The uterine artery Doppler and the umbilical artery were abnormal in eight and eight cases respectively. A discordancy between the umbilical artery size was present in six cases. Abruptio placentae occurred in three cases. A strong association between hypertensive disorders and fetal growth restriction was found in our series and in literature. CONCLUSIONS: The sonographic presence of thick heterogeneous placenta is strongly associated with an adverse pregnancy outcome and often with perinatal death.

Perinatal outcome of fetuses with a birth weight greater than 4500 g: an analysis of 3356 cases.

OBJECTIVE: To assess the perinatal outcome in a series of macrosomic fetuses according to the intended mode of delivery, and to estimate the individual risk of shoulder dystocia and brachial plexus injury upon information available either prior the onset of labor or at delivery. STUDY DESIGN: Perinatal and postnatal information of 3356 women who delivered during a 10-year period a macrosomic fetus (>4500 g) in vertex presentation were analyzed. After the exclusion of cases with extraneous factors that may have affected the health of the neonate, patient and neonatal characteristics were compared according to the intended mode of delivery. The contribution of factors known prior labor and at the time of deliver on the occurrence of shoulder dystocia and brachial plexus injury was analyzed using multiple logistic regression analysis. RESULTS: During the study period, 2371 women were admitted to spontaneous labor, 778 underwent an induction of labor, and 207 had an elective cesarean section. All cases of shoulder dystocia (n=310), and brachial plexus injury (n=94) occurred among women who delivered vaginally. The rate of brachial plexus injury was higher in cases who had shoulder dystocia than in those who did not (58/310 versus 36/2329, P<0.001). The incidence of brachial plexus injury increases steadily from 0.8 in fetuses weighing 4500-4599 g to 2.86% in those weighing more than 5000 g (P<0.01) and from 2.1 in women taller than 180 cm to 12.5% in those shorter than 155 cm (P<0.05). After adjustment for confounding variables shoulder dystocia (OR 9.2, 95% C.I. 5.38; 15.59), operative vaginal delivery (OR 1.96, 95% C.I. 1.10; 3.49) and clavicular fracture (OR 2.9, 95% C.I. 1.31; 6.44) remained predictors of brachial plexus injury. CONCLUSION: Since some of these risk factors are known prior to delivery, each woman whose fetus is suspected to weight more than 4500 g should be counseled on her individual risk of severe perinatal morbidity before a decision on the mode of delivery is taken.

Percutaneous treatment of placenta percreta using coil embolization.

PURPOSE: To report the use of embolotherapy to avoid hysterectomy in rare placenta percreta. CASE REPORT: A pregnant 34-year-old woman (gravida 3, para 2) was admitted with premature rupture of membranes and vaginal bleeding in the 32nd week. Prenatal B-mode and Doppler ultrasound revealed marked hypervascularity of the placenta with disruption of the uterine-bladder interface consistent with placenta percreta. Since the patient insisted on uterine preservation, uterus and placenta were left in situ after caesarean section, which was followed by coaxial microcoil embolization of 6 pelvic arteries and postoperative methotrexate administration. Three months later, the patient had severe bleeding from the retained placenta, possibly under the influence of anticoagulation administered for pulmonary embolism. Emergent hysterectomy was performed. CONCLUSIONS: Coil embolization may avoid immediate hysterectomy and reduce peri-delivery blood loss in placenta percreta. However, retained placenta poses a serious risk, even after months, and secondary hysterectomy should be performed as an elective procedure after embolization.

Longitudinal measurement of peak systolic velocity in the fetal middle cerebral artery for monitoring pregnancies complicated by red cell alloimmunisation: a prospective multicentre trial with intention-to-treat.

OBJECTIVE: To evaluate the utilisation measurements of peak systolic velocities in the middle cerebral artery combined with B-mode ultrasound imaging to predict anaemia in an unselected population of pregnancies complicated by alloimmune antibodies known to cause immunological hydrops. DESIGN: Prospective study on an intention-to-treat basis. SETTING: Multicentre study in five large tertiary referral centres. POPULATION: One hundred twenty-five fetuses with maternal alloantibodies known to cause immunological hydrops. METHODS: If peak systolic velocity and B-mode scan were reassuring the pregnancy was monitored at 7-14 days interval. If either method showed signs of anaemia, an umbilical fetal blood sampling was performed. When the gestational age was greater than 35 weeks, labour was induced. MAIN OUTCOME MEASURE: Moderate to severe anaemia at delivery. RESULTS: Overall sensitivity to detect moderate to severe anaemia below 35 weeks (haemoglobin level below 0.65 multiples of median) was 88%. Specificity was 87%; positive predictive value was 53% and negative predictive value was 98%. The diagnosis of severe anaemia was missed in one fetus; however, the final outcome was good. The method was not useful after 35 weeks. CONCLUSIONS: Middle cerebral artery peak systolic velocity is a highly sensitive non-invasive means for determining the degree of anaemia present in red blood cell alloimmunised pregnancies. The widespread use of the Doppler method will minimise fetal complications associated with amniocentesis and fetal blood sampling. Non-invasive measurement of middle cerebral artery peak systolic velocities is more convenient and acceptable to alloimmunised pregnancies and may significantly lower health care costs. A Doppler interval of seven days is recommended.