HSG (Hysterosalpingography) & Advanced Diagnostic Tests

Infertility is usually considered a problem if a couple hasn’t conceived after 12 months of regular unprotected sex. Female infertility can be due to ovulatory disorders, tubal disease, uterine abnormalities, endometriosis or unknown cause. Assessment of female reproductive tract is an important part of the evaluation for infertility.

Hysterosalpingography (HSG) is an imaging procedure that uses fluoroscopy (x-rays) to check the shape of the uterus and the condition of the fallopian tubes by introducing a radiopaque dye into the uterus through the cervix. Tubal factors are responsible for almost 30-40% of women’s infertility, making HSG a useful initial investigation.

Over the last several years, there have been advances in technology that have resulted in the development of minimally invasive, highly accurate diagnostic techniques that are complementary and/or alternative to HSG in selected patients. You need to select the right type of diagnostic test based on the clinical history, patient’s preference and the suspected pathology.

What does Hysterosalpingography (HSG) mean?

HSG is a special type of X-ray using a dye that is radio-opaque (will show up on an X-ray film), and is used to determine whether the uterus and fallopian tube are open.

The dye is injected through the cervix under an X-ray that is capable of seeing the dye as it passes through the uterus and fallopian tube.

This is often done on days 7 to 10 of the menstrual cycle when women are in the proliferative phase to lessen the chance of disrupting a pregnancy in its early phase.

What are the indications for the HSG?

The typical symptoms are:

• Assessing the infertility of women.
• Recurrent pregnancy loss.
• Suspected tubal obstruction.
• Congenital uterine anomalies.
• Intrauterine adhesions (Asherman syndrome).
• A tubal surgery, such as a reversal, or tubal sterilization reversal may be followed by an assessment to determine if the procedure was successful.
• Evaluation of recurrent failed implantation.

What is the procedure of HSG?

The process is as follows:

• Patient is on the fluoroscopy table.
• A speculum is placed in the vagina.
• An antiseptic solution is used to clean the cervix.
• A special cannula or a catheter is placed into the cervix.
• Slowly, dye is injected into the uterus.
• The fluoroscopic X-ray is taken as the dye makes its way to the uterus and fallopian tubes.
• When obtained by contrast spillage is free in the pelvic cavity, the tube is patent.
• This typically takes 10-20 minutes.

What abnormalities are revealed by HSG?

HSG can identify:

• Tubal blockage – either proximal or distal.
• Hydrosalpinx
• Uterine fibroids – only submucous
• Endometrial polyps.
• Congenital uterine malformations.
• Intrauterine adhesions.
• Uterine septum.
• Union of the horns of the uterus.
• Foreign body in the uterus.

What are the benefits of HSG?

Advantages include:

• Simple outpatient procedure.
• Relatively inexpensive.
• High sensitivity (tubal patency).
• Describes key anatomical information.
• May temporarily enhance fertility (after flushing of tubes with contrast medium).
• Widely available.

What are the restrictions on HSG?

Limitations include:

• The patient has been exposed to ionizing radiation.
• Discomfort or pain due to the procedure.
• Tubal blockage from tubal spasm (false positive).
• Lack of adequate evaluation of conditions of the pelvis, like endometriosis.
• Unable to evaluate the function of the ovaries.

What kind of problems can arise following an HSG?

HSG is generally safe, but can be complicated by:

• Pelvic infection.
• Contrast dye allergy (needle puncture).
• Vaginal spotting.
• Uterine perforation (rare).
• Vasovagal reaction.
• Pain or cramps in the pelvis.
• Some women who are at high risk for developing pelvic inflammatory disease may be advised to take preventive antibiotics.

What are some diagnostic tests that are used in addition to or in place of HSG?

There are a number of modern investigations that are also diagnostic.

Saline Infusion Sonography (SIS):

• Use of echo to visualize the lungs during airless inflation.
• SIS is the injection of sterile saline into the uterine cavity while using transvaginal ultrasound.

Advantages:

• No radiation exposure.
• Improved visualization of endo-polyps.
• Detects submucosal fibroids.
• Identifies intrauterine adhesions.

Hysterosalpingo-Contrast Sonography (HYCOSY)

HYCOSY uses ultrasound contrast agents instead of X-rays.

Advantages:

• No radiation.
• Evaluates tubal patency.
• Comfortable outpatient procedure.
• Real-time assessment.

Hysteroscopy

Hysteroscopy is regarded as the best method to examine the uterine cavity.

Advantages:

• Direct visualization.
• Simultaneous diagnosis and treatment.
• Removal of polyps.
• Adhesiolysis
• Septum resection.

Laparoscopy with Chromopertubation

Laparoscopy is used to directly assess pelvic organs and methylene blue dye is used to check tubal patency.

Advantages:

• The best available method for evaluating the tubal condition.
• Diagnosis of endometriosis
• To detect adhesions in the pelvis. To be able to identify pelvic adhesions.
• Therapeutic interventions that occur during the same therapy

Uses:

• Congenital uterine anomalies
• Adenomyosis
• Deep infiltrating endometriosis
• Complex Müllerian anomalies

What are the merits of HSG over high level diagnostic tests?

When is an advanced diagnostic test preferred over HSG?

Advanced investigations are suggested when:

• The results of the HSG procedure are not conclusive.
• Endometriosis is suspected.
• There is a failure to achieve repeated implantations.
• The diagnosis of congenital uterine anomaly should be confirmed.
• History of previous surgery of the pelvis.
• Treatment will be expected.

Hysterosalpingography is still one of the most significant initial tests used for infertility diagnostics because of its simple nature and effectiveness in investigating tubal patency and pathologies of uterine cavity.

Nevertheless, there are many limitations of this test in diagnosis of pelvic diseases not associated with uterus cavity. Modern methods of infertility diagnosis, such as hysteroscopy, laparoscopy, HYCOSY, saline infusion sonography, and MRI have greatly improved the process of diagnosing infertility and sometimes even allowed to combine diagnosis and treatment in one procedure.