Hysterosalpingography (HSG)
What is a hysterosalpingogram? (a sample X-ray is at the bottom of this page)
A hysterosalpingogram is an important test that is part of the basic infertility evaluation.
The test is usually done in the radiology department of a hospital in which radiographic contrast (dye) is injected into the uterine cavity through the vagina and cervix. The uterine cavity fills with dye and if the fallopian tubes are open the dye will then fill the tubes and spill out into the abdominal cavity. In this way it can be determined whether the fallopian tubes are open or blocked and whether the blockage is located at the junction of the tube and the uterus (proximal) or whether it is at the end of the fallopian tube (distal). These two areas where the tube is most commonly blocked have different causes. Effective treatment for tubal factor infertility is available.
There are other things that potentially can be seen on a hysterosalpingogram other that whether the tubes are open or blocked. The uterine cavity is evaluated for the presence of polyps or fibroid tumors or scar tissue. The fallopian tubes are also examined for any defects within the tube or suggestion of a partial blockage.
What to expect during a hysterosalpingogram
The hysterosalpingogram study only takes about 5 minutes to actually perform. However as the test is usually done in the radiology department of a hospital there is additional time for the woman to register at the facility and fill out a questionnaire and answer some questions regarding allergies to medication etc. The way the test is done is the following:
- The woman lies on the table on her back and brings her feet up into a "frog leg" position.
- The doctor places a speculum in the vagina and visualizes the cervix.
- Either a soft, thin catheter is placed through the cervical opening into the uterine cavity or an instrument called a tenaculum is placed on the cervix and then a narrow metal cannula is inserted through the cervical opening.
- Contrast is slowly injected through the cannula or catheter into the uterine cavity. An x-ray picture is taken as the uterine cavity is filling and then additional contrast is injected so that the tubes should fill and begin to spill into the abdominal cavity. Additional x-rays are taken as this "fill and spill" occurs.
- When both tubes are demonstrated to be patent (or blocked), the woman is usually asked to roll to one side or the other slightly to give a slightly oblique x-ray image which may help to further delineate her anatomy.
- The procedure is now complete. The instruments are removed from the cervix and vagina. The woman usually remains on the table for several minutes to recover from the cramping which usually accompanies injection of the contrast.
- After several minutes the woman can get dressed and leave the hospital.
The results of the test are immediately available. The x-ray
pictures can be reviewed with the woman several minutes after the procedure has
been completed if both she and the physician prefer to do this.
Pregnancy rates in several studies have been reported to be slightly increased in the first months following a hysterosalpingogram. This may be due to the fact that the flushing of the tubes with the contrast could open a minor blockage or clean out some debris that may be a factor that is preventing the couple from conceiving. Some of these studies suggest that using oil based contrast provides a greater increase in pregnancy rates after a hysterosalpingogram than does the use of water based contrast.
Complications
Complications associated with a hysterosalpingogram include the possibility of an allergic reaction to the dye, which is uncommon. This usually manifests as a rash, but can rarely be more serious.
Pelvic infection or uterine perforation are also possible complications. Both of these are very uncommon.
If a woman has multiple sexual partners or is otherwise at risk for sexually transmitted diseases, she should be screened with cervical cultures before doing an HSG. Some physicians prescribe several days of antibiotics for their patients to attempt to reduce the risk of infection after HSG.
Normal hysterosalpingogram