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Old June 28th 05, 11:44 PM
Circe
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"oregonchick" wrote in message
...
My ob casually asked me as I was preparing to leave my last appt if I
wanted to have this test done. I had never heard of it before, and I
asked her to explain. She mentioned it was to find out if the baby was at
risk of spinal cord problems, but didn't really elaborate. She seemed busy
and annoyed at the question. Is this something that everyone has done?

In a nutshell, the AFP is a blood test performed on the mother at around
mid-pregnancy. The blood is analyzed and higher/lower concentrations of
certain hormones *can* be indicative that the fetus is at a
higher-than-expected risk of some types of defects, including spina bifida
and trisomy (Down Syndrome, which is T21, being the most common). If the
result of an AFP test is "positive" for any of these conditions, further
testing can be done (amniocentesis in the case of a trisomy, high level
ultrasound in the case of spina bifida) to determine whether or not there is
actually a problem.

It is important to understand that the AFP is only a screening test. A
"positive" result on the test does not mean there is certainly something
wrong, only that the amount of hormone in your blood stream suggests a
higher-than-expected chance that there is something wrong. The AFP is
generally recommended because it is a non-invasive test that poses no risks
to the fetus or the mother, but tends to be fairly accurate in identifying
women for whom further, more invasive testing (read amnio) might be
warranted. That doesn't mean that most women who are referred for further
testing due to AFP results wind up having babies with problems, but rather
that most women who *do* have babies with these sorts of problems are
identified by the AFP.

Before consenting to taking the AFP, you need to decide whether or not you
would consent to further testing if the result is positive. It's also worth
noting that the results are considerably less accurate for women over about
37-38--the tendency is for almost all tests done on women above that age
bracket to come back positive. Also, the usefulness of the AFP as a test for
spina bifida is somewhat overrated, IMO. Unless you would not have a
standard anomaly scan at 20ish weeks of pregnancy, it isn't likely to result
in finding a problem you wouldn't otherwise have discovered. So what the AFP
is *really* doing for you is screening for trisomies.

I am sorry to hear that your practitioner did not explain all of this to you
and that she seemed annoyed by the question. This is not appropriate
behavior on the part of a physician, IMHO. In addition to evaluating whether
or not you want the AFP, I would recommend evaluating whether or not you
wish to continue in the care of a practitioner who does not answer your
questions and treats you rudely. That does not seem like a particularly
positive harbinger for her bedside manner or her ability to get informed
consent before performing other procedures when you are giving birth.
--
Be well, Barbara