Fig 1.
Flow diagram of cases included in the sequential screening.
Table 1.
Overall, first and second trimester results of contingent screening for Down syndrome alone and for Down syndrome and trisomy 18 combined.
Fig 2.
FISH signals on fetal cells in maternal blood.
a) Dual-probe FISH analysis with two probes for different loci on chromosome 18 shows three signals in green and three in red in a pregnant woman with a trisomy 18 fetus; b) FISH analysis with two probes for chromosome 21 showing three signals in green and three in red specific for two different loci of chromosome 21 in a woman with a trisomy 21 fetus.