Hysterosalpingography (HSG): Procedure Guide for Radiologic Technologists

What Is Hysterosalpingography?

Hysterosalpingography (HSG) is a fluoroscopic examination of the cervical canal, uterine cavity, fallopian tubes, and peritoneal spill after transcervical administration of iodinated contrast. It is an established test in infertility evaluation, particularly for tubal patency and tubal architecture. It also depicts the cavity outline, but ultrasound, sonohysterography, hysteroscopy, or MRI may characterize uterine and adnexal disease better.

As a radiologic technologist, you may be called upon to assist with HSG procedures in the fluoroscopy suite or interventional radiology setting. Understanding the indications, technique, contrast choices, normal radiographic anatomy, and pathologic findings supports diagnostic-quality studies and appropriate patient care. This guide is an educational overview, not a substitute for supervised training, product labeling, or local protocol.

Indications for HSG

HSG is primarily performed as part of the infertility workup, but it has several other important indications:

• Evaluation of tubal patency — The most common indication. Determining whether one or both fallopian tubes are open is critical for guiding fertility treatment decisions, including whether in vitro fertilization (IVF) may be necessary.
• Assessment of the uterine cavity — HSG can identify congenital uterine anomalies (septate, bicornuate, unicornuate, didelphys uterus), submucosal fibroids, endometrial polyps, intrauterine adhesions (Asherman syndrome), and postsurgical changes.
• Post-tubal ligation evaluation — Confirming tubal occlusion after sterilization procedures or assessing the proximal and distal tubal segments before reversal surgery.
• Evaluation of recurrent pregnancy loss — HSG may reveal a cavity abnormality, although ultrasound/sonohysterography, hysteroscopy, or MRI is often needed for definitive characterization.
• Postoperative assessment — Following myomectomy, septoplasty, or adhesiolysis to confirm a normal cavity.
• Tubal recanalization guidance — In some interventional settings, HSG is used as a roadmap for fluoroscopically guided fallopian tube catheterization.

Contraindications and Precautions

Knowing the contraindications is just as important as knowing the indications. Performing an HSG in an inappropriate clinical setting can lead to serious complications.

Do Not Proceed

• Pregnancy or possible pregnancy — HSG is contraindicated because it combines an intrauterine procedure with pelvic radiation. Exclude pregnancy by menstrual/sexual history and testing when indicated under local policy; a test is particularly appropriate with irregular cycles or an atypically light last period.
• Ongoing pelvic or reproductive-tract infection — Active PID, salpingitis, or cervicitis/endocervicitis should be treated and the examination rescheduled.
• Active vaginal or uterine bleeding — Reschedule active bleeding; the ACR notes that chronic spotting is not necessarily prohibitive and requires physician review.
• Relevant severe prior contrast reaction — “Iodine allergy” is not a diagnosis. Ask specifically about prior allergic-like or unknown reactions to iodinated contrast. A severe prior reaction contraindicates HSG in most cases; a moderate reaction may contraindicate it unless no suitable alternative exists. Any decision to use premedication or a different examination belongs to the supervising physician and does not eliminate reaction risk.

Cautions and Product-Specific Restrictions

• Recent uterine/cervical instrumentation or surgery — Obtain physician review and follow the relevant product label and surgical protocol. Specifically, FDA labeling contraindicates Lipiodol HSG within 30 days of curettage or conization; there is no universal “6–8 week” rule for every procedure or contrast agent.
• Severe cervical stenosis — May prevent cannula placement and increase the risk of uterine perforation.
• Prior PID or suspected tubal disease — This increases post-HSG infection risk and may change antibiotic management; it is not the same as active infection.
• Oil-based contrast considerations — Lipiodol is contraindicated in hyperthyroidism, hypersensitivity to Lipiodol, marked cervical erosion, and known or suspected reproductive-tract neoplasia, among other label restrictions. Avoid it in severe lung impairment, cardiorespiratory failure, or right-sided cardiac overload. The ACR recommends normal thyroid function before oil-based contrast and follow-up monitoring because retained iodine may cause hypo- or hyperthyroidism. FDA labeling requires a negative pregnancy test within 24 hours before Lipiodol HSG. During breastfeeding, use shared clinician decision-making and consider thyroid testing in the exposed infant as the FDA label advises.

Patient Preparation

Proper patient preparation affects study quality, safety, and comfort. The technologist's role may include screening, setup, imaging, documentation, and assistance, but who may perform cervical instrumentation or administer contrast depends on licensure, supervision, credentialing, and local policy.

Pre-Procedure Checklist

• Exclude pregnancy — Document menstrual and pregnancy history and apply the facility's testing policy. A same-day urine or serum hCG is not universally mandated by the ACR for every HSG, but testing should be considered for irregular cycles, atypically light bleeding, uncertain dates, or other pregnancy possibility. If Lipiodol is planned, its FDA label requires a negative pregnancy test within 24 hours before administration.
• Consent and time-out — The qualified practitioner explains expected discomfort, benefits, alternatives, and risks (infection, bleeding, allergic-like reaction, perforation, intravasation, and agent-specific risks) and obtains consent according to law and facility policy. Confirm patient, procedure, pregnancy status, and contrast before starting.
• Screen for prior contrast reaction — Document the specific agent, symptoms, severity, and treatment. Do not equate shellfish allergy or povidone-iodine sensitivity with iodinated contrast allergy. The supervising physician determines whether an alternative test, agent substitution, or premedication is appropriate.
• Bowel preparation — An enema or bowel prep is not routinely required but may be considered if the pelvic anatomy is difficult to visualize on the scout image.
• Analgesia and selective antibiotics — A nonopioid analgesic such as an NSAID may be considered on the day of HSG if not contraindicated. Routine antibiotic prophylaxis is not required for every low-risk patient. It may be prescribed before HSG for prior PID; if dilated or obstructed tubes are found in a patient not already receiving prophylaxis, the physician should consider antibiotics. One guideline-supported regimen is doxycycline 100 mg twice daily for 5 days, but allergies, pregnancy possibility, local resistance, and clinician orders govern.
• Bladder emptying — Patients are commonly asked to void for comfort and pelvic positioning; follow local protocol.
• Positioning — Begin supine in lithotomy or modified lithotomy for sterile cervical access. Table configuration, leg supports, and later repositioning are equipment- and protocol-specific.

Contrast Media and Equipment

Contrast Media Options

The choice between oil-based and water-based contrast media has clinical implications that affect both image quality and patient outcomes. Understanding the differences is important for the ARRT exam and for assisting the radiologist.

Equipment Setup

Before the patient enters the room, verify that the following equipment is ready:

• Fluoroscopic unit — C-arm or fixed fluoroscopy table with pelvic imaging capability, pulsed fluoroscopy, last-image-hold/save-grab, and appropriate dose reporting. DSA is not routinely required.
• Contrast and warming — Verify the ordered agent, route, expiration, and product-specific instructions. If the facility warms contrast, use an approved controlled device and follow infection-control policy; warming is not a universal requirement.
• HSG tray or cannula kit — Typically includes a vaginal speculum, atraumatic grasping instrument or tenaculum if needed, purpose-designed uterine cannula or HSG balloon catheter, sterile drapes, sponges, and a mucosa-appropriate antiseptic selected under facility policy.
• Syringe and tubing — A secure syringe/tubing system of suitable capacity for the ordered agent and anticipated volume, prepared so that all air can be removed.
• Sterile lubricant — For speculum insertion.

Step-by-Step HSG Procedure

The following is a representative sequence, not a substitute for the supervising physician's protocol, state scope-of-practice rules, device instructions, or contrast labeling. The examination is performed under a qualified physician's supervision and interpreted by a licensed physician.

Step 1: Scout Image

A scout (pre-contrast) pelvic image may be obtained when indicated by local protocol to assess positioning or identify radiopaque material that could confound interpretation. It is not an ACR-mandated exposure for every patient. Center and collimate to the anatomy needed for the clinical question rather than automatically exposing the entire bony pelvis.

Step 2: Sterile Preparation and Cannula Insertion

Using aseptic technique, the operator inserts a speculum, prepares the cervix according to local policy, and accesses the cervical canal or endometrial cavity with an appropriate cannula or catheter. A tenaculum is used only when needed; less traumatic approaches can reduce cervical pain. Prime the system vertically to remove air. For a balloon catheter, use only the manufacturer-specified inflation medium, location, and minimum effective volume—overinflation can cause pain, obscure pathology, or injure the uterus.

Step 3: Contrast Injection Under Fluoroscopy

Administer the smallest appropriate amount of the ordered contrast slowly under intermittent, preferably pulsed fluoroscopic observation. Select the lowest pulse rate that preserves the information needed; a fixed 2–4 pulses/second is not appropriate for every system or clinical situation. Do not inject against marked resistance or severe pain. Avoid overdistending a hydrosalpinx. Monitor continuously for intravasation and stop if it occurs—immediately when oil-based contrast is used.

• Initial filling — The radiopaque uterine cavity usually has a smooth triangular configuration; early filling can reveal defects hidden by full distention.
• Tubal filling — As injection continues, contrast flows into the cornua (the horn-shaped upper corners of the uterine cavity) and enters the fallopian tubes. Each tube is followed from the interstitial segment (within the uterine wall) through the isthmus (narrow proximal portion), the ampulla (wider distal portion), and finally to the fimbriated end.
• Peritoneal spill — Free intraperitoneal spill from a tube supports patency of that tube. Spill may disperse around bowel or layer dependently; it need not pool specifically in the rectouterine pouch. Delayed or loculated spill can suggest fimbrial disease or peritubal adhesions but is not direct visualization of adhesions.

Step 4: Spot Images

Multiple spot images are obtained during the examination:

• Early filling image — Shows the uterine cavity before complete distention (useful for detecting small polyps or adhesions that could be masked by overdistention).
• Full distention image — Shows the fully opacified cavity contour and larger filling defects; remember that HSG has limited sensitivity for polyps and submucosal fibroids.
• Tubal phase images — Document each tube through the fimbrial end when it opacifies, including the level and pattern of any nonfilling.
• Peritoneal spill image — Demonstrates free spill. Oblique, prone, or other views may be used selectively to display the full tube or resolve overlap; reposition only when safe.
• Balloon-deflated / postdrainage image — If a balloon was used, final imaging with it deflated permits assessment of the lower cavity and cervix. A postdrainage image may be obtained when endometrial pathology is suspected; voiding and proof of “complete tubal emptying” are not routine diagnostic requirements.

Normal Radiographic Anatomy vs. Pathologic Findings

Interpreting HSG images requires familiarity with normal anatomy and the ability to recognize common pathologic patterns. The following comparison table summarizes key findings every rad tech should know for the ARRT exam.

Common Uterine Anomalies Recap

For the ARRT exam, you should be able to differentiate the following congenital uterine anomalies based on their HSG appearance:

• Septate versus bicornuate configuration — Both may produce two endometrial channels on HSG. Intercornual angles are not sufficiently reliable for definitive classification because HSG does not depict the external fundal contour. Three-dimensional ultrasound (with or without saline infusion) is generally first-line for uterine shape; MRI is an alternative when needed. Hysteroscopic septum incision is an individualized specialist decision, not an automatic consequence of an HSG appearance.
• Unicornuate uterus — A single, banana-shaped cavity with a single fallopian tube. Often associated with a rudimentary horn on the contralateral side (which may or may not communicate).
• Uterus didelphys — Two completely separate uteri, each with its own cervix. May be associated with a longitudinal vaginal septum.
• T-shaped cavity — A narrow cavity with thickened lateral walls; historically associated with in-utero diethylstilbestrol (DES) exposure but not specific to it.

Radiation Dose Considerations

HSG uses ionizing radiation in the pelvis, so pregnancy exclusion, examination justification, and ALARA optimization are essential. Do not label an organ absorbed dose in mGy as “effective dose” (reported in mSv). Published doses vary substantially with equipment, patient size, fluoroscopy time, number of acquisitions, and protocol; a single universal HSG dose is misleading. The exposure does not remain in the body and has not been shown to harm a pregnancy conceived later in the same cycle, but HSG must not be performed when pregnancy is suspected.

Dose Optimization Strategies

• Pulsed fluoroscopy — Use the lowest pulse rate and dose mode that preserve diagnostic information. Do not treat one pulse rate or percentage reduction as universal across systems.
• Last-image-hold (LIH) — Use LIH for documentation instead of taking separate spot images whenever possible.
• Collimation — Tightly collimate to the pelvic region. Avoid including the iliac wings or proximal femurs unnecessarily.
• Keep beam-on time and acquisitions to a minimum — Use short intermittent observations and avoid unnecessary repeats; no fixed time limit determines whether an individual examination is acceptable.
• Use magnification selectively — Electronic/magnification modes can increase dose, but the ACR notes that magnification is often useful for detailed tubal imaging. Use it only when the added detail is diagnostically needed.
• Grid removal — For smaller patients, consider removing the anti-scatter grid if the system allows it and image quality remains acceptable.
• Patient shielding — Do not place gonadal shielding in the field. Routine contact shielding of out-of-field organs such as the thyroid provides little benefit and can obscure anatomy or trigger automatic exposure changes if it enters the field; follow current facility/medical-physics policy. Collimation and technique optimization are more effective.

Post-Procedure Care and Complications

Immediate Post-Procedure Care

After removing the catheter/cannula and speculum, assess symptoms and assist the patient upright when clinically ready; a mandatory 5–10-minute supine period is not evidence-based for every patient. Provide agent- and facility-specific written instructions:

• Activity — Most patients can resume usual activity the same day as tolerated. Driving restrictions depend on sedation (usually not used), pain, vasovagal symptoms, and local policy.
• Expected symptoms and red flags — Mild cramping and light spotting can occur for 1–2 days. Fever, increasing or persistent pelvic/abdominal pain, heavy or unusual bleeding, foul-smelling discharge, rash/swelling, breathing difficulty, chest pain, confusion, or neurologic symptoms requires prompt assessment; breathing or neurologic symptoms are an emergency, especially after oil-based contrast.
• Medication — Take antibiotics only when prescribed and complete that prescribed course. Do not imply that every patient needs doxycycline.
• Pelvic activity — Evidence and institutional instructions vary regarding intercourse, tampons, swimming, or douching. Follow the performing service's written instructions rather than a universal 48–72-hour restriction.
• Oil-based contrast — Follow the clinician's thyroid-monitoring plan. Because retained ethiodized oil can affect maternal and fetal/neonatal thyroid function, tell the clinician about subsequent pregnancy and report symptoms of thyroid dysfunction.
• Follow-up — The interpreting/referring clinician reviews results on the service's usual timeline. A normal HSG does not exclude endometrial, myometrial, ovarian, or peritoneal disease and does not by itself determine fertility treatment.

Complications to Recognize

HSG vs. Alternative Imaging Modalities

Patients undergoing infertility workup may also receive other imaging studies. Understanding the strengths and limitations of each modality helps you answer exam questions and counsel patients.