Genetic Testing for Inheritable Diseases, Recurrent Miscarriages

All healthy humans are born with 46 chromosomes that are part of every cell in the body. Chromosomes are divided into 22 matching pairs and one pair of sex chromosomes. These cell structures each carry the genetic material, or DNA, that makes every individual unique.

You receive genes from both of your biological parents; half from your mother and half from your father. The genes determine which features you inherit, such as hair and eye color, blood type, and other characteristics — like your father’s nose or your mother’s mouth.

Inheritable Diseases

You also inherit, via genes, the risk of developing certain diseases. For example, hemophilia and Tay-Sachs disease are inherited diseases that can be passed on from parents to children. These diseases are due to defects in the chromosomes.

You may be aware of amniocentesis and chorionic villus sampling (CVS), both of which are genetic tests that can be performed while you are pregnant and can determine the baby’s health and sex. If, however, you are having problems getting pregnant or have a history of miscarriages, there is a test you can take before you get pregnant to see if your infertility problems are due to a genetic defect. The test is called the karyotype test.

Genetic problems with the embryo or fetus are responsible for a high percentage of pregnancy losses before 12 weeks.

The Karyotype Test

Usually done as a blood test, a karyotype looks at the structure, number and arrangement of chromosomes found in a sample of cells. This test may also be called a chromosome analysis.

If you have had recurrent miscarriages, or if there is no sperm in your partner’s ejaculation, the two of you should both be tested. During the karyotype test, the cells are processed and photographed to determine if there are any missing or extra chromosomes or if there are any structural changes that could prevent you from getting pregnant or cause miscarriages.

You should be aware that this test can also determine if you have a defective chromosome that can lead to problems with a baby’s development or growth. Even if you and your partner are healthy, one of you might carry a gene that can increase your risk of having a baby with birth defects.

The results of genetic testing may be emotionally difficult to handle. For this reason, it is important to talk with your fertility doctor about the pros and cons of taking this type of test.