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91.
In order to gain more insight into the association between alpha-fetoprotein (AFP) and fetal chromosomal disorders, especially Down's syndrome, we measured AFP in fetal serum, amniotic fluid, and maternal serum at cordocentesis. We compared the concentration and gradient of AFP in these three compartments. Our data confirm earlier findings on second-trimester fetal serum AFP concentration. The results indicate that low maternal serum AFP in pregnancies with fetal chromosomal disorders could result from an impaired fetal kidney function as well as from impaired membrane or placental passage of AFP, rather than from reduced fetal AFP production.  相似文献   
92.
A 21 -year-old woman with progressively deforming or type III osteogenesis imperfecta (OI) presented for prenatal counselling and diagnosis at 10 weeks' gestation. Family history was non-contributory. At 14.8 weeks' gestation, ultrasonographic examination revealed fetal skeletal hypomineralization, easily compressible fetal cranium, and thickened long bones, indicating that the fetus was also affected. Confirmation of the prenatal diagnosis of OI type III was made following a Caesarean section birth of a male infant with multiple skeletal deformities and blue sclerae implying, in this case, autosomal dominant inheritance.  相似文献   
93.
94.
A case of fetal loss due to infection after first-trimester chorionic villus sampling is described. The fetus was born at 18 3/7 weeks and showed an annular constriction of one of the arms as seen in the amniotic band sequence. Induction of congenital defects might be one of the complications of chorionic villus sampling.  相似文献   
95.
Volumes of feto-maternal transfusions (FMTs) in transabdominal chorionic villus sampling (TACVS) in the second trimester of pregnancy were calculated from the difference between maternal alpha-fetoprotein (AFP) concentrations before and 1 h after TACVS. In 50 pregnancies, there existed no correlation between FMT volume and the amount of villi collected or the number of TACVS attempts. The expected risk of fetal exsanguination due to very voluminous FMT could not be substantiated. In one case, immunization could have been the cause of hydrops fetalis, although only a volume of 0.15 ml could be calculated.  相似文献   
96.
Magnetic resonance (MR) imaging was performed at 29 weeks of pregnancy after ultrasonographic detection of an abnormal cleft in the fetal brain. Fetal neuromuscular blockade was induced by pancuronium bromide injected into the umbilical vein under continuous ultrasound (US) guidance. MR images supported the echotomographic diagnosis of schizencephaly improving the visualization of symmetrical broad clefts connecting the lateral ventricles with the subarachnoid space. Schizencephaly was finally confirmed by neonatal US, computed tomography, and MR.  相似文献   
97.
We report a female infant noted prenatally to have an umbilical cord mass. At birth, a labial strawberry haemangioma was noted. She subsequently developed an abdominal mass which was discovered to be a proliferating haemangioma, continuous with both the labial and the umbilical stump lesions.  相似文献   
98.
We report a case of chromosomal mosaicism for monosomy 21 revealed in amniotic fluid cell culture. Ultrasound examination at 19 weeks' gestation showed in utero growth retardation and a complex cardiac malformation. A repeated amniocentesis confirmed the presence of monosomy 21 mosaicism. In view of the sonographically detected fetal abnormalities, termination of pregnancy was elected.  相似文献   
99.
Three fetuses with TAR (thrombocytopenia with absent radii) or TAR variant syndrome were found to be thrombocytopenic during the third trimester of the pregnancy. These findings indicate that fetal blood sampling, besides ultrasonography, skeletal radiographs, or even fetoscopy, may indeed contribute to the prenatal diagnosis of TAR syndrome, and thus may help in differentiating TAR syndrome from other syndromes with malformations of the upper limbs.  相似文献   
100.
The fetal loss rates and fetal congenital birth defects in 821 transabdominal (TA) chorionic villus sampling (CVS) and 771 amniocentesis (AC) cases were evaluated from a 5-year period (1987–1991) at the University Central Hospital of Turku. The parents were given the option of choosing between the two sampling procedures. CVS was performed, in most cases, at 11 weeks of gestation; and AC, at 15 weeks. The rate of total post-procedure loss was 6·7 per cent in the CVS group and 4·4 per cent in the AC group (p=0·08). The rate of spontaneous abortions was 1·9 per cent in the CVS group and 1·0 per cent in the AC group (p=0·10). The number of birth defects was low in both study groups. No limb reduction cases were observed. Mosaicism was noted in 14 CVS cases and in five AC cases. We conclude that TA-CVS is a safe and practical alternative to AC in prenatal fetal karyotyping.  相似文献   
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