Chromosome analysis of fetuses in risk pregnancies.

Adult Amniotic Fluid/cytology Cells, Cultured Chromosome Aberrations/diagnosis,genetics Chromosome Disorders Down Syndrome/diagnosis,genetics Female Fetal Diseases/diagnosis,genetics Hemophilia A/genetics Humans Infant, Newborn Karyotyping Male Maternal Age Metabolism, Inborn Errors/diagnosis,genetics Methods Phenotype Pregnancy Prenatal Diagnosis