HYSTEROSALPINGOGRAPHY (HSG) – Tubal Patency Test

HSG! why to get this investigation? how? where? when it’s done? what information does it give? how it’s helpful?

This blog would answer these common queries about (HSG) hysterosalpingography, a very important basic investigation of fertility workup for women that evaluates cavity of uterus and patency of fallopian tubes and also guides for appropriate treatment options.

What is HSG?
It is a X-ray film of pelvis area, that outlines uterine cavity and tubes. If tubes are patent then it shows spill of contrast in abdominal cavity.

When is it performed?
It is performed immediately after periods finish, 7 to 10 days or first half of a menstrual cycle; in order to avoid X-ray radiation if there are any chances of pregnancy.

Is it painful?
Yes, it causes discomfort and pain in lower abdomen due to stretching of cervix and uterine cavity, but it does not require a general anesthesia. Simple painkillers and muscle relaxants are helpful.

How long it takes for the test?
It usually takes 5 to 10 minutes but can vary from patient to patient.

What is the preparation before test?
Pain killers and muscle relaxants are given before the procedure.

How is HSG performed?
A catheter is passed through cervix, and a radio opaque contrast medium is inserted by a syringe attached to the catheter. The contrast goes in the uterine cavity and then flows towards the tubes and then out into the abdomen. This contrast appears white on X-ray films outlining uterine cavity and tubes.

Are there any problems after procedure?
The procedure can lead to:

• pain 
• discomfort in lower abdomen
• mild bleeding
• discharge

Are there any complications of HSG?
There are some complications for which you have to seek medical help urgently, such as:

• severe abdominal pain
• heavy bleeding
• fever
• fainting
• foul smelling discharge
• infection
• reaction to contrast (in rare occasions)

Are there any post-procedure care?
It’s an outpatient or office procedure but in case of pain or bleeding, then the patient is observed for few hours. The patient is advised to take rest and use pain killers and muscle relaxants.

What is a normal uterus appearance on HSG?
The normal size uterus appears as a smooth cavity, with two tubes showing a free spill.

What HSG tells about development of reproductive tract?
During fetal life:

• a uterus is developed by fusion of two right and left tubes (paramesonephric ducts)
• the proximal unfused part forms fallopian tubes  
• and distal fused part forms uterus, cervix  and upper part of vagina

HSG can show any defect in the development of these parts.

What information does HSG give about size of uterus?
Ultrasound gives a more precise information about uterine size. HSG tells about cavity size and shape, small sized uterus (hypoplastic uterus) has small cavity.

What HSG tells about shape of uterus?
HSG tells about the shape of uterus, whether it is normal or different. Different shapes include:

• Uni-cornuate uterus (single horn) with one tube, when only one paramesonephric duct formed during fetal time.
• Bicornuate uterus (two horns) with two tubes, when two paramesonephric ducts failed to fuse at the upper part.
• Uterus Didelphys with two tubes, two uterus, and two cervix. This happens when two tubes totally fail to fuse.

What HSG shows about cavity of uterus?
It can show any abnormal septum, adhesions, fibroids, cyst, or any false passage. All these interfere with implantation of pregnancy or cause abortions.

What HSG tells about tubes?
The shape of tubes tells about any structural defect, adhesions (beading), blockage site and size, any dilatation due to infections or fluid collection (hydrosalpinx), tubal patency is also confirmed.

Why it’s important to know tubal patency?
Tubes are the site where pregnancy starts, fertilization (meeting of sperm and egg) occurs and it implants in uterus. If tubes are blocked or damaged then it would result in inability to conceive.

How knowing about tubal patency affects treatment plans?
If tubes are blocked on HSG, then it should be followed by laparoscopy for further investigations and treatment, such patients will not be benefited by IUI (intra uterine insemination). Only bypassing of tubes through assisted reproductive techniques of IVF or ICSI (in vitro fertilization) would be helpful.

Does HSG increases pregnancy rates?
During HSG procedure, there is endometrial (lining of uterus) scratching which increases blood flow and thickness of uterine lining, passage of contrast through tubes may also increase chances of conception.

Remember, if you are trying to conceive then your uterus, ovaries and tubes should be working  normally along with precise balance of hormones. HSG is a very affective test for tubal evaluation and management of fertility problems.

Dr. Ayesha Azam Khan