Background. Pregnancy with concomitant chorioangioma and placental mesenchymal dysplasia (PMD) coexisting with a normal viable fetus is very rare. The literature was reviewed to explore the incidence and genetic origin of this condition. Case. The case was first identified by prenatal ultrasonography, but the prenatal diagnosis only included chorioangioma. PMD was then confirmed during postnatal evaluation, which included gross and histologic examination of the placenta. The macroscopic and microscopic findings were consistent with concomitant chorioangioma and placental mesenchymal dysplasia during pregnancy. Genetic findings confirmed genetic similarity of the chorioangioma and vesicle-like villi with the fetus. Conclusions. The case represents a rare placental abnormality whose pathogenesis and molecular basis need further research. Detailed histologic and genetic analyses are essential for accurate and differential diagnosis.

Prenatal BACs-on-Beads™ (PNBoBs™) technology has been approved for use in routine clinical prenatal diagnosis in numerous countries. However, the influence of data interpretation on the accuracy of the results remains to be evaluated. The present study aimed to determine the accuracy of existing data interpretation approaches and develop an optimization method to improve the performance of the PNBoBs™ assay in prenatal diagnosis. A total of 2,289 prenatal cases with known karyotypes and raw ratio data from PNBoBs™ assays were recruited for the present study. Positive results, according to the data interpretation methods used for the PNBoBs™ test, were validated against current gold-standard approaches. Statistical analyses were then performed to evaluate the accuracy of existing methods in data interpretation to provide a basis for the optimization of a follow-up approach. Among the existing methods, the 'trimmed standard deviation threshold' approach had the highest sensitivity and false-positive rates, with 98.1 and 4.2%, respectively. The 'n-1 or greater probes' rule had the highest specificity (99.7%) and the second-highest false-negative rate (11.5%). The method optimized in the present study provided a reasonable balance between sensitivity (98.1%) and specificity (99.6%) with regards to the interpretation of the data obtained from the PNBoBs™ assay. The results indicated that the present optimization method outperforms existing approaches in data interpretation for the PNBoBs™ assay, and as a result, may reduce unnecessary verification turnaround time and cost in prenatal diagnosis.

The objective of this study was to investigate, retrospectively, the frequencies of fetal chromosomal abnormalities identified in 4176 prenatal cytogenetic examinations at the Xiamen Maternity and Child Health Care Hospital over the 5-year period from October 2005 to September 2010. The frequency of abnormal fetal karyotypes was 4.6%. Numerical chromosome abnormalities were identified in 150 cases. The frequency of trisomy 21 was by far the highest, followed by trisomy 18. Structural aberrations of chromosomes were identified in 43 cases, including 21 cases with balanced and 22 cases with unbalanced chromosomal aberrations. In addition, 16 cases of apparently de novo chromosomal aberrations and 27 cases of familial inheritances were observed. Increased awareness of the frequencies of fetal chromosome abnormalities is important for the improvement of prenatal care and providing the options of termination or continuation of the pregnancy. Data obtained in this study provide the basis of a database for genetic counseling.

Aim. Achondrogenesis type II is a rare, lethal osteochondrodysplasia with considerable phenotypic heterogeneity. We describe our experience in diagnosing prenatal-onset achondrogenesis type II by a multidisciplinary assessment. Methods. Two cases of fetal achondrogenesis type II were analyzed retrospectively using prenatal ultrasound evaluation, postnatal radiographic diagnosis, and molecular genetic testing of COL2A1. Results. A causative mutation in the COL2A1 gene was found in both patients. Combined with postnatal radiographic examination, the final diagnosis of achondrogenesis type II was made. Conclusion. Our findings emphasize the importance of a multidisciplinary assessment for the definitive diagnosis of achondrogenesis type II, which is paramount for proper genetic counseling.