Miscarriage And Why It Happens
A: Unfortunately miscarriages are extremely common. They occur in one of every five pregnancies. So although there are 4 million babies born in the United States each year, another one million couples undergo the emotional trauma of having a miscarriage. Having practiced obstetrics over the last 22 years I have seen thousands of couples go through miscarriages. They occur so commonly, I generally see to two to three such couples a week. No matter how sophisticated a woman and her partner may be, no matter how many healthy children they might already have, a miscarriage is always an extremely upsetting event.
Q: Are there different types of miscarriages? A: Yes. The majority of miscarriages--60 percent or so--come about because of a miscombination of the chromosomes of the egg and sperm when they fuse at conception. Four out of five times when the egg and sperm fuse a healthy embryo results. One out of five times, however, the chromosomes of the egg and sperm don't combine correctly resulting in the embryo having abnormal chromosomes.
But there are other causes for miscarriage as well. These range from abnormalities of a woman's reproductive organ -- such as a uterus that has large fibroids--to hormonal inadequacy, infection or harmful environmental influences.
Q: Is it useful to try to detect the specific cause for every
miscarriage?
A: Since 60 percent of all miscarriages occur because of the accidental
event of chromosomal miscombination, trying to find the "cause" of this
random event will not help a couple avoid a similar outcome in a future
pregnancy. However, if there is some reason to suspect that another
factor is at work -- such as an anatomic, hormonal, environmental,
infectious, or genetic abnormality -- then further testing is appropriate.
Such testing may enable a treatment to be found that can significantly
increase the chances of the next pregnancy being successful.
Since women who have had three or more miscarriages are more likely than others to have a specific, nonrandom cause for their miscarriages, it is worthwhile for such women to undergo a comprehensive evaluation. By so doing, a treatable cause for these recurrent miscarriages can often be found.
Q: Is there anything a woman can do during pregnancy to reduce her risk?
A: First of all, she should take several steps to prepare for becoming
pregnant. This means getting medical problems attended to, having
dental work done and making sure immunizations are up to date.
Second, she should make sure that while trying to get pregnant she is eating a healthy, well balanced diet and is getting some source of folic acid. Taking a standard over-the-counter multivitamin tablet most easily does this. Folic acid decreases the risk of spinal cord defects developing in the baby.
Third, a woman trying to conceive should reduce the amount of alcohol she consumes and stop smoking. She should of course stop the use of all recreational drugs and consult her doctor before taking any medications other than Tylenol or antacids.
Fourth, all women and their partners should inquire of family members about their genetic and family health histories. This way the possibility of any inheritable diseases can be uncovered and professional genetic counseling obtained if necessary.
Fifth, while trying to get pregnant and during pregnancy it is important
to make sure that the environment in which a woman lives and works does
not contain any noxious substances that might be
harmful to the pregnancy. While there are many more factors that
contribute to reduced risk for miscarriage and that are discussed in my
book, these are the most important ones.
Q: Will doctors ever find a way to prevent miscarriages?
A: The answer to this question depends on what kind of miscarriages we
are discussing. As far as the spontaneous, common miscarriage that
occurs randomly because of miscombination of the chromosomes of the egg
and sperm, the answer is probably no. On the other hand, miscarriages
caused by anatomic problems, hormonal inadequacy, medical illnesses or
environmental factors are certainly amenable to being reduced or
eliminated.
Q: What advice can you offer women who have suffered a miscarriage and
are now scared about it happening in another pregnancy?
A: Your fears and concerns are entirely normal and appropriate. However
as you learn more about miscarriages you will come to understand that
the vast majority of women who go through 1, 2, or even more
miscarriages do eventually go on to have as many healthy children as
they want. My advice to you is to find out as much about miscarriages
as possible, consult with your doctor as to whether or not further
testing makes sense for you, and then move on with the assurance that
your next pregnancy is overwhelmingly likely to be a normal one
resulting in the birth of a healthy baby.
![]()