Rh Factor Questions
Seventeen years ago, I may have suffered a miscarriage. I am Rh negative and did not receive a RhoGAM shot at the time. Four years later, I had an abortion and did receive the shot. I'm now 36 and recently received RhoGAM again after suffering a miscarriage at eight weeks. Could my first (possible) pregnancy, with no shot, be affecting my ability to take a pregnancy to term now? Can we prevent this from happening again?
Question:Peg Plumbo CNM
Peg Plumbo has been a certified nurse-midwife (CNM) since 1976. She has assisted at over 1,000 births and currently teaches in the... Read more
Although Rh disease can cause miscarriage, it would probably have to be quite severe to cause this at eight weeks. I doubt this to be the cause of the miscarriage(s). Rh hemolytic disease is a progressive attack of the maternal antibodies against the baby's red blood cells.
It is easy to get a titer to see if you are sensitized. A blood test with a titer of 1:16 or greater means that some sensitization has occurred. However, this is routinely done before the administration of RhoGAM. Call your clinic and they can tell you what your titer is. If they did not do it, it is simple to collect.
Some providers do not feel it is cost-effective to do a work-up until a woman has miscarried twice or even three times. This is due to studies which show that most women will retain the third pregnancy (or fourth) just as successfully whether an investigation is made or not. I feel that other factors must be considered, however, and age is one of them. 50 to 60 percentof all early spontaneous abortions are associated with a chromosomal abnormality, but without an obvious, strong family history, genetic testing is not usually done after one or two miscarriages. However, a thyroid study (a test for autoantibodies) and antiphospholipid antibodies, including the lupus anticoagulant and anticardiolipin antiodies, could be done now.
Rarely, inadequate progesterone from the corpus luteum (where the egg ruptures) can cause miscarriage. Measuring progesterone and doing an endometrial biopsy following ovulation can sometimes diagnose this problem.
From a nutritional and environmental perspective, unless deprivation or exposure is extreme, these are rarely causes of recurrent miscarriage. Coffee consumption in excess of four cups per day has been associated with miscarriage in some studies and, of course, smoking and alcohol consumption have been implicated as well. I would also eat a well-balanced diet.
Observing cervical-mucus changes (see other letters or go to a person knowledgeable about the Billings method of natural family planning), or taking your basal body temperature is often just as effective as investing in ovulation kits.
Because of your age, I would try to convince your provider that you need testing done now or at least make one visit to a reproductive endocrinologist to assist in conception soon.
I hope all goes well for you.
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