what is karyotype
Guide. Karyotype is a test to identify and evaluate the size, shape, and number of chromosomes in a sample of body cells.Extra or missing chromosomes, or abnormal positions of chromosome pieces, can cause problems with a person's growth, development, and body functions. Find out whether a chromosome defect is present in a fetus. 2  Karyotyping also may be done to find out whether chromosomal problems may have caused a fetus to be stillborn. 3  Find out the cause of a baby's birth defects or disability.