The HSG ( hysterosalpingogram, X-ray of the uterus and tubes) is one of the commonest tests done for evaluating the fertility of a woman . It is done to confirm that the uterine cavity is normal and the fallopian tubes are open.
What makes this test special is the fact that it is only done for one reason - to test the fertility of a woman. However, since it is only done for infertile women, this means this test if often misinterpreted. Let me explain.
Many women have minor anatomic variants of their uterine cavity . A common example is an arcuate uterus ( in which the upper border of the uterine cavity is curved rather than straight).
An arcuate uterus is something which many fertile women have as well. However, neither they nor their doctor knows they have an arcuate uterus, because they have enough sense not to get a HSG done.
This means that the only HSGs a doctor sees are HSGs done for women who are infertile. Because of this , every time the doctor sees this finding, he chooses to (mis) interpret this as an "abnormality" and happily jumps to the conclusion that this is the reason for the infertility.
The doctor is happy, because he has made the right "diagnosis" and found the problem ! The patient is happy too, because she feels she has finally found a very competent doctor , who has been able to diagnose the cause - something which all the other doctors had overlooked . This diagnostic acumen testifies to his superior skills and competence.
The trouble, of course, is that this minor anatomic variant is of no clinical importance and does not affect fertility at all ! However, the minute the doctor finds the '" problem" , he needs to treat it. Overdiagnosis leads inexorably to overtreatment, and many of these patients end up being subjected to useless procedures such as hysteroscopic metroplasty, which can actually end up reducing their fertility !