Objective To assess the types and numbers of cases, gestational age at specific prenatal diagnosis and diagnostic accuracy of the diagnosis of skeletal dysplasias in a prenatal population from a single tertiary center. (88% and 89%, respectively) at the first diagnostic examination. Methods

The enrichment of fetal erythroblasts from the peripheral blood of pregnant women is currently actively pursued for the development of a non-invasive means of prenatal diagnosis. Since erythroblasts in maternal blood are not all of fetal origin, and currently no reliable method exists to distinguish between the maternal and fetal erythroblasts, their use for prenatal diagnosis is not without uncertainty. The purpose of this study was to determine the percentage of fetal erythroblasts in maternal blood at the single cell level and to what extent such cells can reproducibly be used for polymerase chain reaction (PCR)-based prenatal diagnostic analyses. Erythroblasts were enriched from the peripheral blood of rhesus negative pregnant women using magnetic cell sorting (MACS). Single erythroblasts identified morphologically were individually micromanipulated and analysed by a multiplex PCR reaction for the fetal SRY and rhesus D genes. As a control for the PCR reaction the beta-globin gene was used. The PCR results were validated by the results obtained by invasive procedures. In all instances where single erythroblasts were examined, the correct fetal genotype for the two fetal specific loci was detected. Furthermore, our results indicate that approximately 50% of the enriched erythroblasts are of fetal origin.

Objective To compare the sonographic findings of the nasal bone in fetuses with trisomy 21 with pathomorphological findings to determine whether the bone is truly absent.Methods Seventeen first-trimester fetuses with trisomy 21 were identified; the median gestational age was 12 weeks (range, 11-14) and the median maternal age was 38 (range, 27-47) 'present' and 'absent', but instead between 'normal' and 'hypoplastic'. For reproducible results it is necessary to standardize the sonographic examination. The sonographic landmarks of the fetal nose are: the nasal bone, the skin above and the cartilaginous tip of the nose.

In Germany, Austria and Switzerland the results of screening for chromosomal defects by measurement of fetal nuchal translucency thickness, in centers with appropriately qualified sonographers and using The Fetal Medicine Foundation's software, are similar to those reported in the UK using the same methodology.

The lack of B19V-IgG in fetuses with B19V-derived anemia or hydrops is most likely due to a limited materno-fetal transfer of IgG and a poor fetal antibody response. Fetal B19V infection is poorly controlled in the absence of specific antibodies.