This radiological test reveals information about the internal cavity of the uterus and whether or not the fallopian tubes are open (patent). It can be performed in the radiology suite of a hospital or in a clinic. A catheter is inserted into the cervix and is held in place by an inflatable balloon. Radiographic contrast (dye) is injected and the uterine cavity fills. X-ray pictures are taken during the procedure.
The uterine cavity is evaluated for the presence of congenital uterine anomalies, polyps, fibroids, or scar tissue. The dye should then travel through the fallopian tubes and spill into the pelvic cavity. This shows whether the fallopian tubes are open or blocked; if blocked, it can show us where the blockage occurred (proximal—near the uterus, midpoint, or distal—near the end of the tube). If the dye spills into the pelvic cavity and collects in an abnormal way, it may suggest pelvic scar tissue. Pregnancy rates in some studies have been reported to be slightly increased in the first months following a HSG. This is possibly due to the flushing of debris through the tube or the clearing of a minor blockage.