Preterm delivery rate and fetal outcome in structurally affected twin pregnancies: A retrospective matched control study

Data from 23 twin pregnancies with one structurally affected fetus were compared with data from 23 twin pregnancies with proven absence of structural fetal anomalies and matched for maternal age, parity, and year of delivery. The preterm delivery rate ( < 37 weeks) was high in both groups but not significantly different (57 vs. 48 per cent). Perinatal mortality was significantly higher in the structurally affected twin pregnancies (65 vs. 9 per cent). In the affected twins, birth weight of the anomalous fetus was significantly lower than that of the normal co-twin. Since there was no difference in the incidence of maternal disease (hypertensive disorders, diabetes), it was concluded that the higher perinatal mortality was determined mainly by the nature of the anomaly and not by the preterm delivery rate.     

β-Glucuronidase activity in mouse oocytes,mouse preimplantation embryos,and human gametes

A microfluorimetric assay was designed to monitor β-glucuronidase (β-gluc) activity during the early development of mouse embryos and was also applied to measure β-gluc activity in human sperm cells and single human oocytes. Mouse oocytes and preimplantation embryos at different stages of development, failed fertilized human oocytes, and human sperm cells were collected, and β-gluc activity was analysed. In the mouse, β-gluc activity could be measured starting from the morula stage on in a pooled sample of 15 embryos and at blasto-cyst formation in one single embryo. β-Gluc activity was low in human sperm cells. The enzyme could be readily demonstrated in 87 per cent of non-fertilized human oocytes. Considerable variation in β-gluc activity was noticed between individual oocytes.     

Congenital generalized cystic lymphangiomatosis diagnosed by prenatal ultrasound

We describe a previously unknown congenital abnormality of the lymphatic system, characterized by multiple cystic lesions of the lower extremities and thorax. Diagnosis was made by ultrasound in the second trimester. The ultrasound findings, pathology results, and differential diagnosis are presented.     

Prenantal diagnosis of X-linked hydrocephaly

A case of X-linked hydrocephaly is presented. Early second trimester evaluation of the size of the lateral cerebral ventricles resulted in onemale fetus cfontinuing further normal developmentand one male fetus being abroted because of progressive hydrocephaly. The affected fetus was characterized by cerebral ventricular dilation without aqueductal stenosis. This case history shows the feasibility of early monitoring of pregnancies at risk of X-linked hydrocephaly. In some cases, ventricular enlargement rather than aqueductal stenosis may be the primary lesion.     

In utero ultrasonographic features of campomelic dysplasia

A prenatal diagnosis of campomelic dysplasia in a primigravida is described. First level fetal ultrasonography demonstrated bowing and shortening of lower limbs. Second level examination allowed the correct diagnosis by demonstrating several skeletal anomalies pathognomonic of campomelic dysplasia.     

Neonatal form of the hyperornithinaemia,hyperammonaemia, and homocitrullinuria (HHH) syndrome and prenatal diagnosis

We describe here the first case of neonatal death due to the hyperornithinaemia, hyperammonaemia, and homocitrullinuria (HHH) syndrome and the first prenatal diagnosis of this disorder in a subsequent pregnancy in this family.     

Prenatal diagnosis of lissencephaly

We report two cases of prenatal detection of lissencephaly by high-resolution ultrasound. The first case studied was referred for high-risk obstetrical management and serial antenatal ultrasounds because of a family history of lissencephaly in an unresolved chromosomal abnormality. Diagnosis of a smooth gyral pattern consistent with lissencephaly was made at 32 weeks' gestation. The second case was referred for prenatal ultrasound because of a size versus dates discrepancy. The ultrasound examination showed a smooth gyral pattern at 31.5 weeks. In light of this ultrasound finding, a fetal blood sample was obtained and a chromosomal abnormality reported, confirming the diagnosis. To our knowledge, these cases represent the first report of the sonographic prenatal diagnosis of cerebral agyria or lissencephaly.     

Characterization of i(18p) in prenatal diagnosis by fluorescence in situ hybridization

A case is presented in which chorionic villus direct preparation and cultured chorionic villus cells revealed a 47,XX, + mar karyotype. The marker was a small metacentric chromosome and appeared to be i(18p)—isochromosome 18p. Follow-up studies in both amniotic fluid and fetal fibroblasts confirmed the karyotype. In order to characterize the marker, a panel of biotinylated DNA probes was used, including a whole chromosome 18 probe, chromosome 18-specific alpha satellite DNA, Yac clones, and a pan-telomeric probe. These studies show that the marker is a monocentric i(18p) in which about 80 per cent of chromosome 18 alpha satellite DNA has been lost.     

The early diagnosis of neural tube defects

The sonographic diagnosis of fetal neural tube defects (NTDs) has been enhanced by the recognition of associated brain and skull anomalies. Previous reports have found these anomalies to be accurate in predicting spina bifida after 16 weeks' gestation, and an inverse correlation was suggested between the presence of these sonographic markers and gestational age. Therefore, we assumed that early second-trimester sonography would be at least as accurate as that performed after 16 weeks' gestation. To examine this hypothesis, we looked for the presence of these cranial sonographic markers suggestive of open NTDs in 8011 low-risk cases, using transvaginal sonography (TVS), between the 12th and 17th week of gestation (menstrual age). Fetal NTDs were identified in ten cases (l.25%o). The NTDs were cervico-cranial in three, lumbo-sacral in six, and thoracal in one of the ten cases. None of the seven cases examined was dyskaryotic. Cerebellar dysmorphism, ‘banana’ sign, cerebellar absence, and hypoplasia were detected in all the low NTDs, usually before the detection of the spinal lesion. All the sonographically diagnosed malformations were confirmed by post-abortal examination except in one case, where the patient decided to continue the pregnancy and refused follow-up. We therefore conclude that transvaginal sonographic examination of the fetal skull before the 17th week of gestation is an accurate method for the detection of low NTDs.     

Fetal akinesia/hypokinesia sequence: Prenatal diagnosis and intra-familial variability

Intrauterine fetal movement plays a key role in normal embryonic and fetal development (Moessinger, 1983). When movement is absent or decreased, abnormal development takes place which can be appreciated in newborns and/or fetuses with the fetal akinesia/ hypokinesia sequence. This sequence is caused by a number of heterogeneous entities which result in decreased fetal movements by the action of intrinsic or extrinsic factors. Prenatal diagnosis of the akinesia/hypokinesia sequence may be possible during the second trimester through the use of real-time ultrasonographic evaluation of fetal movement. We report a family with three consecutive affected pregnancies in which the prenatal presentation of this sequence varied. Based on the phenotypic findings of the three affected fetuses, we believe that although they superficially resemble those features found in the New–Laxova syndrome, they are probably affected with a distinctly different lethal form of akinesia/ hypokinesia transmitted in an autosomal recessive fashion.