Antithyroglobulin Testing

If you've been diagnosed as having idiopathic infertility (fertility of unknown origin), you may be wondering if it's time to give up on having a baby. The answer is: not yet. There are still tests that can be performed to try to determine the obstacle that stands between you and conception. One such test is the antithyroglobulin test.

Recurrent Miscarriage

The antithyroglobulin tests measures levels of antibodies to the proteins produced by your thyroid gland. High levels of these antibodies are a common reason for recurrent miscarriage and unexplained infertility. Thyroglobulin is a protein that is produced by your thyroid gland. The thyroid is responsible for regulating the various hormones that control your heart rate, metabolism, and other body functions.

In healthy people, antibodies are produced to fight invading cells, such as the germs that can make us sick with colds or the flu. But sometimes, the body decides to read normal healthy cells as invaders and produces antibodies to fight them off. Antithyroglobulin is one such antibody. It aims to destroy the protein cells of the thyroid gland, thyroglobulin, which will lead to the ultimate destruction of the thyroid gland.

Antithyroid Antibodies

Often antimicrosomal antibodies, which also act against the thyroid, are found in tandem with antithyroglobulin antibodies in a person's bloodstream. These two antibodies are therefore called antithyroid antibodies.

The connection between infertility and antithyroglobulin is a recent discovery. Antithyroglobulin has a tendency to interfere with the implantation of the embryo. As the embryo attempts to attach itself to your uterus, the antibodies are released and act as toxins, causing the pregnancy to end in miscarriage.

Women found to have high levels of antithyroglobulin antibodies have difficulty conceiving. Furthermore, such women miscarry about twice as often as women who don't have these antibodies. Experts also tell us that 30% of women who experience recurrent miscarriage are found to have high levels of antithyroglobulin or antimicrosomal antibodies in their bloodstreams. The antibody's presence has also been linked to recurrent IVF and recurrent IUI failures.

Test Results

Test results for antithyroglobulin come back as positive, borderline, or negative. Any score of less than 1:72 is considered negative. Borderline results are from 1:72-1:300. Anything higher than 1:300 is considered positive. Should you have a positive result, your physician will likely advise that this is at least a factor in your infertility troubles.

High levels of the antibody indicate that you may have an autoimmune disease. In any event, there are medications that can help reduce the amount of antithyroglobulin in the blood, such as prednisone and dexamethasone. One you bring the levels down, there is every chance you can conceive.