OBJECTIVE To establish an algorithm for first-trimester combined screening for trisomy 21 with biochemical testing from 7 to 14 weeks' gestation and ultrasound testing at 11-13 weeks. METHODS This was a multicenter study of 886 pregnancies with trisomy 21 and 222 475 unaffected pregnancies with measurements of free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein...

Two unrelated newborn infants with multiple malformations were found to have complete trisomy 9 in all cells examined. In both, the phenotype was similar, consisting of characteristic facial appearance (microphthalmia, bulbous nose, micrognathia, cleft palate, low set ears), skeletal abnormalities (dislocated joints, flexion contractures of the fingers), cardiovascular malformations (persistent...

BACKGROUND Historically, 50% of spontaneously expelled abortuses have been thought to be chromosomally abnormal; about 60% are trisomies. In general, trisomy 16 is the most frequent chromosomal abnormality, followed by trisomy 21 and trisomy 22. So far only 1 case of a female fetus with multiple congenital malformations associated with full trisomy 5 has been described. REPORT We present a ca...

Serum concentrations of fetal antigen 2 (FA-2), the amino-propeptide of the alpha1 chain of collagen type I, were measured in peripheral blood from women with normal (n = 234) and trisomy 21 affected (n = 14) pregnancies between 9 and 11 weeks gestation. Serum FA-2 concentrations were seen to be stable throughout this period, and though raised FA-2 concentrations were seen at the 10th week of g...

The results of chromosome analyses on 500 cases of perinatal deaths are reported. It was found that 4.8% were chromosomally abnormal, but 90% of the chromosomally abnormal were either clinically malformed or macerated fetuses. Of the macerated fetuses, 9% were chromosomally abnormal and of these 33% had trisomy 21. The data suggest that the high loss of trisomy 21 fetuses in later stages of pre...

We present the case of a mentally normal 7 year old girl with short stature, scoliosis, atrial septal defect, and dysmorphic features including linear pigmented streaks on the forearms and lower legs. Chromosome analysis of cultured fibroblasts showed trisomy 12 in 9% and 13% of cells from two skin biopsies. Two trisomy 12 cells were found in lymphocytes after analysis of 500 metaphases. Her cl...

the chromosomal abnormalities, it was reported that Down syndrome (trisomy 21) occurs in 1 in 800 [3,4], Edward syndrome (trisomy 18) in 1 in 6,000 [5], and Patau syndrome (trisomy 13) in 1 in 10,000 fetal subjects [6]. Moreover, birth defects from Down syndrome comprise about 26% of all congenital birth defects [7,8]. As maternal age increases, fetal chromosomal aneuploidy becomes more prevale...