What is hysterosalpingography (HSG)?

Hysterosalpingography (HSG) is a fluoroscopic procedure that uses iodine-based contrast media to image the uterine cavity and fallopian tubes. It is primarily used to evaluate female infertility by assessing tubal patency and uterine cavity abnormalities.

When should HSG be scheduled in the menstrual cycle?

HSG is typically performed during the follicular phase, between days 7 and 10 of the menstrual cycle, after menstrual bleeding has stopped but before ovulation. This timing avoids imaging during a potential early pregnancy and provides optimal visualization of the uterine cavity with a thin endometrium.

What contrast media is used for HSG?

Both oil-based (e.g., Lipiodol) and water-based (e.g., Omnipaque, Isovue) contrast media are used for HSG. Water-soluble agents are more common in the United States due to better mucosal coating, faster absorption, and lower risk of granuloma formation. Oil-based agents may improve pregnancy rates post-procedure but carry a higher risk of intravasation and embolization.

What are the contraindications for HSG?

Absolute contraindications include: ongoing pregnancy, active pelvic inflammatory disease (PID), active menstrual bleeding, and known iodine contrast allergy. Relative contraindications include recent uterine surgery, severe cervical stenosis, and current salpingitis.

What does tubal occlusion look like on HSG?

On HSG, tubal occlusion appears as a block to contrast flow within the fallopian tube. Proximal occlusion shows contrast filling only the uterine cavity without tubal opacification. Distal (fimbrial) occlusion, often due to hydrosalpinx, shows dilated, ballooned distal tubes with contrast pooling and no intraperitoneal spillage.

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Hysterosalpingography (HSG): Procedure Guide for Radiologic Technologists

July 5, 2026·Procedures·~2,800 words

What Is Hysterosalpingography?

Hysterosalpingography (HSG) is a fluoroscopic imaging procedure that evaluates the uterine cavity and fallopian tube patency using iodine-based contrast media. It remains one of the most important diagnostic tools in the workup of female infertility, providing real-time anatomical and functional information that no other imaging modality can match.

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, step-by-step technique, contrast choices, normal radiographic anatomy, and pathologic findings is essential for producing diagnostic-quality studies and providing optimal patient care. This guide covers everything you need to know for clinical practice and the ARRT registry.

ARRT Exam Spotlight

HSG questions appear on the ARRT exam under the Fluoroscopy/Interventional Procedures category. You should know the timing within the menstrual cycle, contrast media types, normal filling sequence (uterine cavity → fallopian tubes → peritoneal spill), and key pathologic findings such as hydrosalpinx and intrauterine adhesions (Asherman syndrome).

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 — Uterine cavity abnormalities are implicated in approximately 10–15% of recurrent miscarriage cases.
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.

Absolute Contraindications

Pregnancy — This is the most critical contraindication. A pregnancy test must be confirmed negative before the procedure. The radiation dose and contrast instillation could harm a developing fetus.
Active pelvic inflammatory disease (PID) — Performing HSG in the presence of active infection can disseminate pathogens into the peritoneal cavity, causing peritonitis or sepsis.
Active menstrual bleeding — Contrast may not adequately coat the cavity, and there is an increased risk of intravasation (contrast entering the venous system).
Known iodine contrast allergy — As with any iodinated contrast procedure, a history of moderate-to-severe allergic reaction is a contraindication. Premedication protocols may be considered in mild cases after consulting the referring physician.

Relative Contraindications

Recent uterine surgery — Within 6–8 weeks of endometrial biopsy, dilation and curettage (D&C), or myomectomy, the endometrium may be too fragile.
Severe cervical stenosis — May prevent cannula placement and increase the risk of uterine perforation.
Current salpingitis or cervicitis — Active infection of the tubes or cervix should be treated before the procedure.
Uncontrolled thyroid disease — Iodinated contrast can exacerbate hyperthyroidism in susceptible patients.

Clinical Pearl: Timing Is Everything

HSG is typically scheduled during the follicular phase of the menstrual cycle — days 7 through 10 counting day 1 as the first day of menses. This timing ensures that (1) menstrual bleeding has stopped, (2) the endometrium is thin enough for optimal cavity visualization, and (3) the patient is not yet ovulating, minimizing the risk of imaging during an early undetected pregnancy.

Patient Preparation

Proper patient preparation directly impacts study quality and patient comfort. As the rad tech assisting with or performing the procedure, you play a key role in ensuring readiness.

Pre-Procedure Checklist

Confirm pregnancy status — A urine or serum beta-hCG test is mandatory on the day of the procedure unless the patient is post-hysterectomy or clearly not of reproductive age.
Obtain informed consent — The referring or performing physician must explain the risks (pain, infection, contrast reaction, uterine perforation, intravasation) and obtain written consent.
Screen for contrast allergy — Document any prior reactions to iodinated contrast. If the patient has a history of mild reaction (rash, hives), premedication with antihistamines and corticosteroids may be ordered. Moderate-to-severe reactions (anaphylaxis, laryngeal edema) are absolute contraindications.
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 antibiotics — Prophylactic antibiotics (e.g., doxycycline) are commonly prescribed to reduce the risk of post-procedural PID, especially in patients with a history of tubal disease. Pain medication (NSAIDs) is typically administered 30–60 minutes before the procedure.
Bladder emptying — The patient should void immediately before the procedure. A full bladder obscures the uterine outline and increases patient discomfort.
Positioning — The patient is positioned supine in a modified lithotomy position on the fluoroscopic table, with feet in stirrups and the pelvis at the edge of the table.

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.

Characteristic	Water-Soluble (Iodinated)	Oil-Based (Lipiodol)
Common brands	Omnipaque (iohexol), Isovue (iopamidol), Optiray (ioversol)	Lipiodol (ethiodized poppyseed oil)
Viscosity	Low — easier to inject, better mucosal coating	High — slower injection, thicker consistency
Image quality	Good delineation of mucosal detail; mixes with peritoneal fluid	Excellent contrast density; may obscure small filling defects
Absorption	Rapid — absorbed from peritoneal cavity within minutes	Slow — may persist for weeks; risk of granuloma formation
Post-procedure pregnancy rates	Moderate improvement	Higher pregnancy rates reported in some studies (possible tubal flushing effect)
Risk of intravasation	Lower risk; contrast is rapidly diluted if venous entry occurs	Higher risk of oil embolization — can cause pulmonary embolism in rare cases
Risk of granuloma	Minimal	Higher — residual oil in the peritoneum can cause foreign body granulomas
Cost	Moderate	Higher
ARRT relevance	Most commonly used in US practice	Be familiar with the risks — commonly tested on registry

Equipment Setup

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

Fluoroscopic unit — C-arm or fixed fluoroscopy table with adequate pelvic imaging capabilities, last-image-hold, and digital subtraction angiography (DSA) if available.
Contrast warming device — Warming the contrast to body temperature reduces patient discomfort and cramping during injection.
HSG tray or cannula kit — Typically includes a vaginal speculum, single-tooth tenaculum (or atraumatic forceps), uterine cannula or balloon catheter (e.g., HSG balloon catheter, Rubin cannula, or pediatric Foley catheter), sterile drapes, sponges, and antiseptic solution (povidone-iodine or chlorhexidine).
Syringe and tubing — A 10–20 mL Luer-Lock syringe with extension tubing for contrast injection.
Sterile lubricant — For speculum insertion.

ARRT Exam Tip: Cannula Types

Be familiar with the different cannula types: the Rubin cannula (acorn-tipped, inserted into the external cervical os) is traditional but prone to leakage. Balloon catheters (similar to a pediatric Foley, size 5–8 French) are now more common — the balloon is inflated inside the uterine cavity or cervical canal to prevent contrast backflow. The ARRT exam may ask which cannula is best for patients with cervical incompetence or a patulous cervical os.

Step-by-Step HSG Procedure

The following sequence describes the standard HSG examination from a technologist's perspective. Each step requires coordination between the technologist and the performing physician.

Step 1: Scout Image

Before any instrumentation, a scout (pre-contrast) pelvic radiograph is obtained. The scout image serves several purposes: it confirms correct positioning (centered at the level of the symphysis pubis), evaluates for any radiopaque pelvic calcifications or foreign bodies that could mimic pathology, and establishes a baseline for contrast injection. The collimation should include the entire pelvis from the iliac crests to the pubic symphysis.

Step 2: Sterile Preparation and Cannula Insertion

The physician performs a sterile speculum examination of the cervix. The cervix is cleansed with antiseptic solution, and the anterior lip is grasped with a tenaculum to stabilize the uterus and straighten the uterine-cervical angle. The cannula or balloon catheter is then inserted through the cervical os. For balloon catheters, the balloon is inflated with 1–3 mL of air or saline within the uterine cavity or endocervical canal, then gently retracted to seat it against the internal os.

Step 3: Contrast Injection Under Fluoroscopy

Contrast is injected slowly and steadily under intermittent fluoroscopic guidance (pulsed fluoroscopy at 2–4 pulses per second to minimize radiation dose). The injection is monitored in real time:

Initial filling — The uterine cavity opacifies first, appearing as a triangular (pear-shaped) density.
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 — In a normal study, contrast spills from the fimbriated ends of the tubes into the peritoneal cavity, where it pools in the pouch of Douglas (rectouterine space). This is the definitive sign of tubal patency.

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 — Uterine cavity fully opacified; best for evaluating contour abnormalities, fibroids, and septae.
Tubal phase images — Both tubes opacified with contrast extending to the fimbriae.
Peritoneal spill image — Demonstrates free spill of contrast into the peritoneal cavity. Oblique views may be needed to separate overlapping bowel loops or to better visualize each tube individually.
Post-drainage (evacuation) image — After the cannula is removed and the patient voids, a delayed image may be obtained to assess residual contrast and confirm complete tubal emptying.

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.

Structure	Normal Finding	Pathologic Finding	Clinical Significance
Uterine cavity	Smooth, triangular (pear-shaped) contour; homogeneous contrast filling	Irregular contour, filling defects, or distorted shape	May indicate fibroids (submucosal), polyps, adhesions (Asherman syndrome), or congenital anomalies
Uterine septae	Single cavity; no internal division	Septate uterus: a thin septum dividing the cavity partially or completely. Bicornuate uterus: two separate cavities with a deep fundal cleft	Septate uterus is surgically correctable (hysteroscopic septoplasty). Bicornuate is associated with higher miscarriage risk
Cervical canal	Smooth, fusiform canal connecting vagina to uterine cavity	Irregular narrowing, filling defects, or fistula tracts	Cervical stenosis may cause difficult cannulation. Fistulae suggest prior surgery or trauma
Cornua (tubal ostia)	Smooth, funnel-shaped openings at the superolateral corners of the cavity	Blunted, occluded, or irregular cornua	Proximal tubal occlusion at the cornual level — may be due to spasm, debris, or true fibrosis
Fallopian tube — Isthmus	Thin, uniform, thread-like proximal segment; smooth walls	Irregular dilation, strictures, salpingitis isthmica nodosa (SIN: multiple small diverticula)	SIN is associated with ectopic pregnancy risk and tubal infertility
Fallopian tube — Ampulla	Wider, gently curving distal segment; smooth mucosal folds	Dilated, sacculated distal tube with no peritoneal spill = hydrosalpinx	Hydrosalpinx is a common cause of distal tubal occlusion; associated with prior PID or endometriosis
Fimbriae / Peritoneal spill	Free spill of contrast from both tubes; contrast pools in the pouch of Douglas (dark, amorphous cloud around the distal tube and uterus)	No spill from one or both tubes; localized spill suggesting peritubal adhesions	Absent spill = tubal occlusion. Loculated spill = peritubal adhesions tethering the fimbriae
Intravasation	Not present	Contrast visible within uterine or ovarian veins — appears as fine, wispy, branching channels extending away from the uterus	Caused by excessive injection pressure, recent uterine surgery, or damaged endometrium. Stop injection immediately if observed
Lymphatic filling	Not present	Contrast in fine, tortuous lymphatic channels near the uterine cornua	Similar etiology to intravasation; more common with oil-based contrast. Usually self-limited

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 uterus — The most common anomaly. A single fundus with a central septum dividing the cavity. The angle between the two horns is typically ≤ 60°. Surgical correction improves pregnancy outcomes.
Bicornuate uterus — Two separate uterine cavities with a deep fundal indentation (>1 cm). The angle between the horns is > 60°. Cannot be reliably distinguished from septate on HSG alone — MRI or 3D ultrasound is needed for definitive diagnosis.
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 uterus — A narrow, T-shaped cavity, most commonly associated with in-utero diethylstilbestrol (DES) exposure.

ARRT Exam Spotlight: Classic Imaging Signs

Memorize these eponymous signs for the registry:
• "Tubal diverticulosis" / Salpingitis Isthmica Nodosa (SIN) — Multiple small, contrast-filled outpouchings along the proximal isthmic portion of the tube, giving a "honeycomb" or "necklace" appearance.
• "Hydrosalpinx" — A dilated, fluid-filled distal tube; appears as a sac-like or "cigar-shaped" structure with no peritoneal spill.
• "Cornual block" — Contrast fills the uterine cavity but does not enter one or both tubes, suggesting proximal occlusion (but must distinguish from transient spasm).
• "Asherman syndrome" — Irregular, angulated filling defects within the uterine cavity representing intrauterine synechiae (adhesions), most commonly post-D&C.

Radiation Dose Considerations

HSG involves ionizing radiation directed at the pelvis, and dose management is a critical responsibility for the technologist. Although the effective dose is relatively low compared to CT (typically 0.5–2 mGy ovarian dose per examination), the ovaries are radiosensitive organs, and many patients undergoing HSG will be attempting pregnancy in the near future.

Dose Optimization Strategies

Pulsed fluoroscopy — Use the lowest acceptable pulse rate (2–4 pulses per second instead of continuous 30 fps). This can reduce dose by 50–80% compared to continuous fluoroscopy.
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 to a minimum — Total fluoroscopy time for a routine HSG should be under 1–2 minutes (typically 30–60 seconds of beam-on time for an uncomplicated study).
Avoid magnification — Use the full field of view; magnification increases patient dose significantly.
Grid removal — For smaller patients, consider removing the anti-scatter grid if the system allows it and image quality remains acceptable.
Shielding — Although the ovaries are in the primary beam, ensure that any radiosensitive tissues outside the collimated field (e.g., the thyroid) are shielded. The use of ovarian (gonadal) shielding is limited during HSG since the ovaries are the primary organ of interest.

Clinical Pearl: Dose Documentation

The ARRT requires documentation of fluoroscopy time and dose (dose-area product, DAP, or air kerma) for every fluoroscopic procedure. As the technologist, you are responsible for recording these values in the patient's exam record. Total fluoroscopy time exceeding 5 minutes should trigger a review of technique and justification.

Post-Procedure Care and Complications

Immediate Post-Procedure Care

After the cannula is removed and speculum withdrawn, the patient should remain supine for 5–10 minutes before slowly sitting up. Post-procedure instructions include:

Activity — Resume normal activities within 1–2 hours. Most patients can return to work the same day.
Symptoms — Mild cramping and spotting are normal for 1–2 days. Severe pain, fever, heavy bleeding, or foul-smelling discharge requires prompt medical evaluation.
Medication — Continue prophylactic antibiotics (typically doxycycline 100 mg twice daily for 5 days) as prescribed.
Activity restrictions — Avoid intercourse, tampons, and douching for 48–72 hours to reduce infection risk.
Follow-up — Results are discussed with the referring physician, usually within 1–2 days. If both tubes are patent and the cavity is normal, the patient may proceed with fertility treatments as planned.

Complications to Recognize

Complication	Incidence	Presentation	Management
Vasovagal reaction	Up to 5%	Bradycardia, hypotension, syncope, nausea	Lie patient flat, elevate legs; atropine if severe; monitor vitals
Pelvic infection (PID)	1–3%	Fever, pelvic pain, vaginal discharge 24–72 h post-procedure	IV/oral antibiotics; may require hospitalization for tubo-ovarian abscess
Contrast intravasation	2–8%	Wispy venous or lymphatic channels seen fluoroscopically	Stop injection immediately; most cases are self-limited; observe for oil embolization if oil-based contrast used
Uterine perforation	<0.5%	Sharp pain; cannula passes beyond expected depth; contrast extravasates into myometrium or peritoneum	Terminate procedure; vital sign monitoring; surgical consult if hemodynamic instability
Allergic contrast reaction	0.2–0.7%	Urticaria, bronchospasm, anaphylaxis	Per departmental contrast reaction protocol (antihistamines, epinephrine, corticosteroids as indicated)
Oil embolization (oil-based contrast only)	Rare (<0.1%)	Respiratory distress, cough, chest pain, hemoptysis during or immediately after procedure	Supportive care, oxygen, anticoagulation in severe cases; pulmonary embolism protocol

When to Suspect Intravasation

Intravasation appears as a fine, feathery, or wispy network of linear opacities extending lateral to the uterus — these are contrast-filled uterine or ovarian veins. If you see this on the monitor, alert the radiologist immediately. The injection should be stopped. Intravasation is more common with: (1) excessive injection pressure, (2) recent endometrial biopsy or D&C (within 6 weeks), (3) use of oil-based contrast, and (4) a damaged or thin endometrium. In most cases, the contrast is rapidly diluted and symptoms are absent, but the exam should be terminated to avoid further venous entry.

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.

Modality	Advantages	Limitations	Primary Use
HSG (fluoroscopy)	Gold standard for tubal patency; real-time dynamic imaging; low cost; can be therapeutic (tubal flushing effect)	Ionizing radiation; iodinated contrast risk; invasive cervical instrumentation; no direct visualization of ovarian or myometrial pathology	Tubal patency, uterine cavity assessment
Hysterosonography (saline infusion sonography — SIS)	No radiation; good uterine cavity detail; can evaluate myometrium and ovaries concurrently	Does not assess tubal patency reliably; operator-dependent	Uterine cavity evaluation (polyps, fibroids, adhesions)
Pelvic MRI	Excellent soft-tissue characterization; no radiation; gold standard for congenital uterine anomaly classification	Expensive; long exam time; does not assess tubal patency; limited availability	Characterizing known uterine anomalies, deep pelvic endometriosis, adenomyosis
Hystero-salpingo contrast sonography (HyCoSy)	No radiation; real-time assessment; can evaluate both cavity and tubal patency	Operator-dependent; requires contrast agent (echogenic); less tubal detail than HSG	Alternative to HSG in some centers for tubal patency screening
Diagnostic laparoscopy with chromopertubation	Gold standard for tubal and peritoneal pathology; can treat pathology concurrently	Invasive; requires general anesthesia; higher cost and risk; does not evaluate uterine cavity without hysteroscopy	Definitive diagnosis when HSG is equivocal or positive for tubal disease

About the author: This guide was prepared by the Radiography 101 Clinical Team, referencing Clark's Pocket Handbook for Radiographers (16th ed.), the ACR Practice Parameter for Hysterosalpingography, and current ARRT exam standards. Content is reviewed for clinical accuracy.