OBJECTIVE To examine whether in pregnancies with fetal trisomy 21 the level of maternal serum free beta-human chorionic gonadotropin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A) at 11 + 0 to 13 + 6 weeks' gestation is independent of the presence or absence of tricuspid regurgitation and to estimate the performance of a screening test that combines tricuspid regurgitation with f...

The management of twin pregnancies discordant for trisomy 21 is dependent on the gestation at diagnosis, chorionicity, and parental preference. Our experience with the management of 15 cases in 1,839 twin pregnancies over a 12-year period is described. Selective termination is not always associated with a successful outcome for the normal co-twin. Two of the three monochorionic twin pregnancies...

While trisomy 21 is a common genetic disorder in singletons, the incidence among identical twins is very rare, occurring in approximately 1-2 per 1000 twin gestations. Trisomy 21 is associated with high incidence of congenital heart defects, and commonly occurs with ventricular septal defects (VSDs). Physiologic burden of VSDs depends on prevalence of anatomic and other circulatory factors. A c...

down's syndrome (ds) is the most common chromosomal abnormality in human. subjects with ds are known to be peridisposed to develop leukemia. the molecular basis of the association between ds and leukemia is unknown. the unscheduled dna synthesis (uds) test measure the ability of dna-repair in mammalian cells after excision of a stretch of dna containing the region of damage induced by chem...

Techniques have been reported in which fluorescence in situ hybridisation (FISH) and cosmid probes are used to detect trisomy 21 (and other abnormalities involving chromosomes X, Y, 13, and 18) on uncultured amniocytes. However the detection rate of trisomy 21 is lower than for the other anomalies owing to a larger number of uninformative results and false negatives. We report the simultaneous ...