Fertility Testing
Recurrent Pregnancy Loss
Tests of recurrent pregnancy loss focus on identifiable causes:
Genetic: Genetic abnormalities are found in approximately 3-5% of couples with recurrent pregnancy loss. The standard genetic test is a karyotype of both partners. The karyotype looks for major abnormalities in the number and/or structure of the chromosomes in an individual. Each person should have 46 chromosomes. Women have two X chromosomes, and a normal female karytope is indicated as 46XX. Men have an X and a Y chromosome and are referred to as XY.
Enivronmental Exposures: Those who work closely with organic solvents, such as benzene, or toxins such as mercury, or radiation may be at higher risk. This is a rare cause of pregnancy loss.
Infections: It is uncertain, but suggested that certain bacterium may cause miscarriage. The most commonly associated organisms are mycoplasma hominis and ureaplasma urealysticum. Cervical cultures are recommended.
Structural: in approximately 10% of RPL cases, benign growths or malformations of the uterus are present. Imaging of the uterus is warranted. Common tests for uterine abnormalities include the HSG and the saline sonogram, as described in Testing For Women.
Hormonal imbalances in thyroid hormone, prolactin, or conditions which cause late ovulation and a short luteal phase can cause miscarriage and should be evaluated. Additionally, diminished ovarian reserve can be a cause of recurrent loss. Simple blood tests and ovulation testing will demonstrate deficiencies.
Blood clotting disorders: Antiphospholipid antibodies (lupus anticoagulant and anticardiolipin antibodies) are strongly associated with recurrent pregnancy loss. A blood test can detect these. If these factors are present, women are generally treated with blood thinning medications (anticoagulants).
There are many other clotting disorders, some of which are more strongly associated with pregnancy loss than others. The two most common disorders that are more consistently associated with recurrent pregnancy loss are Factor V Leiden deficiency and the Prothrombin mutation. Other disorders include low protein C & S activity, MTHFR mutations and elevated homocysteine levels, and antithrombin III deficiencies. Your physician will determine which abnormalities need to be evaluated based on your personal and family histories. Simple blood tests will diagnose these disorders.