As if finding the perfect mate and planning the perfect wedding were not hard enough, some people discover only days before their wedding that they must have a blood test before a marriage license will be issued. Then again, a blood test may be unnecessary. It depends where you live, and, in some states, whether you are a man or a woman. The laws vary from state to state, and in recent years more and more states have dropped the requirement altogether. Is this a good idea? Can your marriage be delayed by the results of these tests? What are the tests for, anyway? Read on to learn about the myths and facts behind premarital blood testing.
Why the "Marriage Blood Test"?
Some people believe that the premarital blood test is to check blood types to be sure you and your future spouse are biologically compatible. (So far, there is no test to determine whether you are otherwise compatible!) While checking the blood type may be helpful in the event of pregnancy — and it is routinely checked then in case a transfusion is needed and to check the Rh type — it is not part of the routine premarital blood test. It is perfectly safe and acceptable for a person of one blood type to marry another with the same or a different blood type. Another myth is that the required blood testing is to make sure you and your betrothed are not related.
In fact, in most locations, the standard premarital blood tests check for evidence of syphilis (now or in the past) and rubella (German measles). Screening for other diseases in future newlyweds has in some cases included tuberculosis, gonorrhea, and HIV; of these, only HIV can be detected by blood tests. Only two states have passed legislation requiring HIV testing before marriage, but those laws did not last long at least in part because of very low detection rates.
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The Policy Behind Testing
The reason for syphilis testing is that detecting this disease before people marry may allow the infected person to be treated before the partner becomes infected. In addition, detecting and treating syphilis in the woman can prevent transmission of the disease and its complications to her fetus in the event of future pregnancy. In this way, transmission through the population could be reduced or even eliminated (though, of course, this assumed that sexual activity was occurring primarily among married people).
When these programs began in the 1930s and 1940s in the United States, syphilis and other sexually transmitted diseases were reportedly very common, especially in big cities. There was considerable fear that syphilis could spread throughout the population — that is, it was truly a public health concern. The discovery of a blood test that could identify past or current exposure to syphilis led to widespread screening programs targeting those about to marry. If evidence of infection was discovered, treatment could be required before the couple could marry.
Although rubella is typically a minor condition in adults, it is serious disease for a developing fetus, especially during the first trimester. It is associated with a high rate of birth defects. Identifying women who are not immune (from previous infection or vaccination) can determine who needs vaccination before pregnancy, a practice that could reduce the chances that a fetus will be affected. If a woman is not immune and has not been vaccinated prior to pregnancy, she will be instructed to avoid anyone who might have the disease. For these reasons, screening women for immunity to rubella before marriage might seem to make sense.
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Abandoning the Test
With the potential to detect and treat syphilis and to protect a developing fetus from rubella or syphilis, why have so many states eliminated the premarital blood testing? The answer is clear: There appears to be relatively little impact on either disease, especially considering the inconvenience and expense of testing all people planning to marry.
Perhaps when sexually transmitted diseases were more common among couples planning to marry, screening made more sense. And, although the problem of sexually transmitted disease has certainly not gone away, studies since the 1970s have demonstrated remarkably few new cases of syphilis detected by premarital blood testing. According to a study in California, only 35 cases were detected among 300,000 persons tested in 1979. This translated into a cost of $240,000 for each case detected!
Another problem is that even if your test indicates no evidence of syphilis just before your wedding, you could get the disease days, weeks or years after the blood test; premarital screening programs cannot do much about that. Presumably, the screening for rubella also has had a small return on the investment, though statistics on this point are not easy to find.
Both tests — for rubella and syphilis — are routinely checked during pregnancy, whether or not they are checked before marriage.
As of May 2002, only seven states (and the District of Columbia) still required a blood test to get married (according to the Colorado Department of Public Health; an updated, centralized list is difficult to obtain). However, many of these last remaining "holdouts" have since dropped the requirement. Only Montana still requires a pre-marital blood test as of September 2012.
Montana — and until quite recently many other states — may have higher rates of syphilis, or lower rates of immunity to rubella among couples planning to marry compared to states that have stopped testing couples. Or, for whatever reason, this state may find that the screening is more effective. It is much more likely, however, that there had not yet been a critical analysis of the usefulness of the testing programs and no one has yet gone to the trouble of introducing new legislation to eliminate them. In the case of Massachusetts, which dropped the requirements for premarital blood testing in 2005, officials stated that the detection rates for syphilis and rubella were nearly zero.
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The Bottom Line
It seems that the days of the premarital blood test are numbered. The resources committed to these programs could probably be put to better use elsewhere. Or, future studies could demonstrate the usefulness of screening for other diseases (that may or may not require blood testing).
In the meantime, if you're a woman planning to get married and living in Montana, you have at least three options: Roll up your sleeves, marry somewhere else, or put off the wedding. Regardless of where you live, talk with your health care professional about your medical history — especially regarding sexually transmitted diseases and any symptoms you may have. After an examination, the two of you can decide whether testing makes sense to reduce the risk of disease for you, your future spouse and any children you may have.
And one more thing: Congratulations!
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Robert H. Shmerling, M.D. is associate physician at Beth Israel Deaconess Medical Center and associate professor at Harvard Medical School. He has been a practicing rheumatologist for over 20 years at Beth Israel Deaconess Medical Center. He is an active teacher in the Internal Medicine Residency Program, serving as the Robinson Firm Chief. He is also a teacher in the Rheumatology Fellowship Program.