What is a hysterosalpingogram (HSG)?
A hysterosalpingogram or HSG is an x-ray procedure used to see whether the fallopian tubes are patent (open) and if the inside of the uterus (uterine cavity) is normal. HSG is an outpatient procedure that usually takes less than 5 minutes to perform.
It is usually done between day 7-9 of menstrual cycle after menstruation has ceased and ovulation has not yet occurred, so that early pregnancies are not disturbed.
Why is HSG done?
While transvaginal ultrasound is done for assessment of uterus and ovaries, normal fallopian tubes cannot be visualized . For an egg and sperm to meet ,it is essential that atleast one tube is open. HSG is done to check if the tubes are open or not.
How is a hysterosalpingogram done?
A woman is positioned under a x-ray imager that can take pictures during the study , on a table. The gynecologist or radiologist then examines the patient’s uterus and places a speculum in her vagina. Her cervix is cleaned, and a cannula is placed into the opening of the cervix. The doctor gently fills the uterus with a liquid containing iodine (a fluid that can be seen by x-ray) through the cannula. The contrast will be seen as white on the image and can show the contour of the uterus as the liquid travels from the cannula, into the uterus, and through the fallopian tubes. As the contrast enters the tubes, it outlines the length of the tubes and spills out their ends if they are open.
Is it uncomfortable?
An HSG usually causes mild or moderate uterine cramping for about 5-10 minutes. However, some women may experience cramps for several hours. These symptoms can be greatly reduced by taking pain killers before the procedure or when they occur.
Spotting sometimes occurs for 1-2 days after HSG.
Are there other options to evaluate tubal patency?
Laparoscopy can also determine if tubes are open, using a procedure called chromopertubation.
An alternative procedure to evaluate tubal patency is a sonohysterosalpingogram (SHG). For SHG, a catheter (narrow tube) is placed in the uterus through the vagina and saline is injected.
When the saline is injected through the catheter slowly your uterus first fills up with fluid.Scanning continues with simultaneous injection of fluid through the catheter. Now this saline overfills the uterus and flows towards the tubes. At this moment your doctor can see the fluid passing out of the tubes and spilling around the ovary. Absence of spill may indicate blockage of the tube of respective side.
However, this procedure is inferior to HSG for assessment of tubal patency.