When The Testing Is Done
Most miscarriages take place within the first 20 weeks of pregnancy and between 10-15% of all pregnancies end up in miscarriage. Often the cause is attributed to chromosome abnormalities and is accepted as that. When multiple losses take place, the American College of Obstetricians and Gynecologists has developed a standard for testing to determine if there may be other causes for the losses. The unfortunate thing is that testing to determine the cause of a missed pregnancy is not done until there have been multiple losses. It is possible that the causes of miscarriages could be discovered earlier and multiple losses avoided if testing was done after the first or second missed pregnancy. Early detection enhances the chances of a normal, healthy pregnancy and live birth.
For losses before 15 weeks, the standard evaluation calls for three specific tests to determine cause - however, these tests often are not enough. Even after the standard testing, 50-75% of couples will remain without answers to their heartbreaking experience of losing multiple pregnancies. The ACOG suggests there be an evaluation of lupus anticoagulant and anticardiolipin antibodies in order to test for antiphospholipid syndrome, parental (as opposed to fetal) balanced chromosome abnormalities, and evaluation for uterine abnormalities. Sometimes answers are found in the standard evaluation, but often more tests are needed.
Other tests and evaluations which are often included by many obstetricians are the evaluation of prolactin levels in order to test for luteal phase defect, TSH to test thyroid function and an evaluation for the presence of Factor V Leiden mutation. Even with all of these evaluations, there are still other possible considerations for the causes of miscarriage. Since research is considered somewhat inconsistent and/or treatment is controversial, some doctors don't test for other possible causes of miscarriage. Some of the other evaluations to consider are PCOS, polycystic ovarian syndrome, bacterial infections or viruses, possible uterine abnormalities and immunology disorders related to reproduction.
After 15 Weeks
While these tests and evaluations are mostly applicable to losses up to 15 weeks, they are also relevant for miscarriages which happen after that period. There are other factors to be considered in later losses and evaluations should include cervical incompetence and thrombophilias.
It is very important to tell your obstetrician about any family history of miscarriages, especially if the losses were late in the pregnancy. This information could suggest conditions which are genetic and the history will help determine a course of treatment.