Of 646 cases involving first trimester chromosome analysis of chorionic villi sam ples obtained by trans cervical aspiration, we found 34 abnormal unbalanced karyo types. In six of these, fetal fibroblast cultures obtained after termination of the preg nancy failed to confirm the abnormality. Three cases were mosaics identified from direct preparations: 46,XY/45,X; 46,XX/47,XX,+3; and 46,XY/47,XY,+18. In two cases of trisomy 16 (46,XY/47,XY,+16; 46,XX/47,XX,+16) and one oftriso my18 (46,XX/47,XX,+18), no mosaicism was detected. In the other 28 cases with unbalanced abnormal karyotypes, there was karyotypic correspondence between villous cells at diagnosis and fetal fibroblasts. References 1. Benn P, Hsu L YF, Perlis T, Schonhaut A (1984): Prenatal diagnosis of chromosome mosaicism. Prenat Diagn 4: 1-9 2. Binkert F, Schmid W (1977) Pre-implantation embryos of Chinese hamster. I. Incidence ofkaryo type anomalies in 226 control embryos. Mutat Res 46: 63-76 3. Boue J, Nicolas H, Barichard F, Boue A (1979) Le clonage des cellules du liquide amniotique, aide dans l'interpretation des mosaiques chromosomiques en diagnostic prenatal. Ann Genet 22:3-9 4. Hahnemann N (1973) Chromosome studies in induced abortions. Clin Genet 4: 328-332 5. Kalousek DK, Dill FJ (1983) Chromosomal mosaicism confined to the placenta in human con ceptions. Science 221 : 665-667 6. Loft A, Tabor A (1984) Discordance between prenatal cytogenetic diagnosis and outcome of pregnancy. Prenat Diagn 4: 51-59 7. Markert CL, Petters RM (1978) Manufactured hexaparental mice show that adults are derived from three embryonic cells.

Long-term Follow-up Results After Aspiration of Chorionic Villi During Early Pregnancy

Chorionic Villi Sampling: General Methodological and Clinical Approach
Chorionic Villi Sampling in a High-Risk Population Using the Portex Cannula
Technical Aspects of Chorionic Villi Sampling in First Trimester Fetal Diagnosis
Single-Operator Aspiration of Chorionic Villi Using an Ultrasound-Guided Silver Cannula
Chorionic Villi Sampling Using Rigid Forceps Under Ultrasound Control
Direct Vision Technique for Chorionic Villi Sampling in 100 Diagnostic Cases
Transabdominal Chorionic Villi Sampling for First Trimester Fetal Diagnosis
Chorionic Villi Sampling by Means of a New Endoscopic Device
A Modified Portex Cannula for Chorionic Villi Sampling
Improved Echogenicity of the Catheter for Chorionic Villi Sampling
Optimal Timing of Chorionic Biopsy and its Application in the Second Trimester of Pregnancy
Microbiology of the Endocervix in Patients Undergoing Chorionic Villi Sampling
Fetoplacental Products as a Prognostic Guide Following Chorionic Villi Sampling
Ultrasonic Observation of Pregnancy During the First Trimester Using a Vaginal Approach
New Sonographic Criteria in Monitoring the First Trimester of Pregnancy
Cytogenetics of Chorionic Villi Sampling: Technical Developments and Diagnostic Applications
Cytogenetic Findings in First Trimester Chorionic Villi Biopsies: A Collaborative Study
Results of 180 First Trimester Direct Chromosome Studies in Chorionic Villi
Mosaicism Confined to Chorionic Tissue in Human Gestations
Discordance Between Prenatal Cytogenetic Diagnosis after Chorionic Villi Sampling and Chromosomal Constitution of the Fetus
Mixed Karyotypes Obtained by Chorionic Villi Analysis: Mosaicism and Maternal Contamination
Culturing Trophoblast Samples
Choice of Medium for Cultivation and 24-Hour Incubation of Chorionic Villi: Selective Effects in Vitro
Histologic Study of Tritiated Thymidine Incorporation by Trophoblastic Villi in the First Trimester
Cytoskeletal and Lectin Markers for Cells Cultured from Chorionic Villi and Decidua
Histomorphological Aspects of Chorionic Villi in First Trimester Fetal Diagnosis
Chromosome Analysis of First Trimester Chorionic Villi Sampled by Chorionscope
Effect of Incubation Time and Serum Concentration on the Number of Mitoses in Aspirated Villi Samples
Freezing of Chorionic Villi
Modified Method for Cytogenetic Studies on Uncultured Chorionic Villi
G-Banding of Chromosomes from Chorionic Villi
Biochemical Analysis of Chorionic Villi: A Worldwide Survey of First Trimester Fetal Diagnosis of Inborn Errors of Metabolism
First Trimester Fetal Diagnosis: Principles and Potential Pitfalls in Enzymatic and Molecular Diagnoses
First Trimester Prenatal Diagnosis of Metabolic Diseases
Comparison of the Activities of 15 Lysosomal Enzymes in Chorionic Villi and in Cultured Amniotic Fluid Cells
Activity of 30 Nonlysosomal Enzymes in Chorionic Villi
Gene Dosage Effect in Chorionic Villi
Prenatal Diagnosis of Menkes' Syndrome by Direct Copper Analysis of Trophoblastic Tissue
First Trimester Diagnosis in a Twin Pregnancy in Which the Mother is a Proven Carrier of the X-Linked Disorder Menkes' Syndrome
Chorionic Biopsy in the Prenatal Diagnosis of Nephropathic Cystinosis
Feasibility of First Trimester Diagnosis of ?-Thalassaemia Using DNA Posymorphisms in the Cypriot Population
Prenatal Diagnosis of ?-Thalassemia by the Analysis of Trophoblast DNA with the Synthetic Oligomer Technique
DNA Polymorphism Analysis in theItalian Population and Prenatal Diagnosis of Thalassemia
First Trimester Diagnosis of Genetic Diseases by DNA Analysis of Chorionic Villi: Preliminary Experience
DNA Polymorphisms and Fetal Sexing for X-Linked Disorders with Chorionic Biopsy
Maternal Cell Contamination of Chorionic Villi Biopsy in a Pregnancy at Risk for Duchenne's Muscular Dystrophy
Pathology of Chromosome Abnormalities in First Trimester Embryos
Assessment of the Safety and Accuracy of Chorionic Villi Sampling in First Trimester Fetal Diagnosis
Methodological Problems in Determining Fetal Loss Rates: Relevance to Chorionic Villi Sampling
Chorionic Villi Sampling: The McGill Randomized Clinical Trial of Safety and Accuracy
Social Aspects of First Trimester Diagnosis
Index of Authors.