A - B - C - D - E - F - G - H - I - K - L - M - N - O - P - Q - R - S - T - U - V - X - Y - Z Karyotype -The chromosomal characteristics of a cell. Karyotyping - A chromosome analysis in which cells are studied to look for abnormalities. Testing a fetus may show if there is a chromosomal reason for the pregnancy loss, which causes about 50% of miscarriages. Testing the parents can help determine if there is an underlying chromosomal problem that increases the chances of repeated losses, which occurs in about 3% of couples with recurrent pregnancy loss. Klinefelter's Syndrome - A genetic abnormality characterized by having one Y (male) and two X (female) chromosomes or a mosaic (a combination of 46XY and 47XX). Klinefelters often causes a fertility problem, though some men will produce sperm. ART and donor insemination are possible. The condition can be passed on.