Hysterosalpingography (HSG)

Hysterosalpingography is a fluoroscopic study of the uterine cavity and fallopian tubes performed by instilling iodinated contrast through the cervix. It is a core investigation in the infertility workup, assessing uterine cavity morphology and tubal patency, and can demonstrate congenital anomalies, synechiae, polyps and tubal occlusion. Timing within the menstrual cycle is important both to avoid an early pregnancy and to optimise image quality.

Indications

Infertility workup to assess tubal patency and the uterine cavity
Recurrent pregnancy loss and suspected uterine cavity abnormality
Suspected congenital uterine anomaly such as septate or bicornuate uterus
Assessment of tubal occlusion, hydrosalpinx or post-reversal patency
Confirmation of tubal occlusion after sterilisation procedures

Contraindications & Cautions

Pregnancy: perform in the early proliferative phase (approximately cycle day 7-10) after menses and before ovulation to avoid irradiating a possible pregnancy
Active pelvic infection or pelvic inflammatory disease: risk of flare and peritonitis
Active uterine bleeding which degrades the study and may embolise clot
Recent uterine or tubal surgery
Iodinated contrast allergy requires an alternative approach or premedication

Patient Preparation

Schedule during the early proliferative phase, typically cycle day 7-10, after bleeding has stopped
Confirm the patient is not pregnant and has abstained or used contraception since the last menses
Screen for and treat pelvic infection; consider prophylactic antibiotics if hydrosalpinx or infection risk
Simple analgesia (an NSAID) beforehand reduces cramping
Explain the procedure, obtain consent and empty the bladder

Technique & Parameters

Position the patient supine in lithotomy and insert a speculum to visualise the cervix
Place a cervical cannula, balloon catheter or vacuum cup and remove the speculum
Obtain a scout image then slowly instil water-soluble iodinated contrast under intermittent fluoroscopy
Acquire spot films of early cavity filling, full cavity distension, tubal filling and peritoneal spill
Oblique views help profile the cornua and unravel overlapping tubes
Instil contrast slowly to avoid venous or lymphatic intravasation and undue cramping

Systematic Review

Assess cervical canal and lower uterine segment
Evaluate uterine cavity contour, size and any filling defects
Inspect the cornua and the interstitial, isthmic and ampullary tubal segments
Confirm free peritoneal spill of contrast around bowel loops on each side
Look for hydrosalpinx, loculation or peritubal adhesions
Note any contrast intravasation into veins or lymphatics

Key Findings & Significance

Free peritoneal spill of contrast confirms tubal patency
Hydrosalpinx: dilated tube with a distended ampulla and absent or loculated spill
Septate uterus: a normal external fundal contour with a partition producing two cavities (best distinguished on 3D imaging)
Bicornuate uterus: two widely divergent horns with a cleft in the external fundal contour
Intrauterine synechiae (Asherman): irregular filling defects and a distorted cavity
Cornual occlusion: abrupt termination of contrast at the uterotubal junction

Differential Considerations

Filling defect in the cavity: air bubble, polyp, submucosal fibroid, synechiae or blood clot
Uterine anomaly: septate versus bicornuate versus unicornuate uterus
Tubal occlusion: true occlusion versus cornual spasm (may relax with time or antispasmodic)
Tubal irregularity: salpingitis isthmica nodosa, tuberculous salpingitis or endometriosis
Beaded tubal contour: tuberculosis or prior pelvic inflammatory disease

Pearls & Pitfalls

Perform between the end of menses and ovulation (about day 7-10) to avoid an early pregnancy and endometrial thickening
Cornual spasm can mimic proximal tubal occlusion; a repeat run or antispasmodic may demonstrate patency
Water-soluble contrast is used; an oil-based contrast flush may have a therapeutic fertility benefit but carries intravasation and granuloma risks
Air bubbles introduced with contrast can mimic polyps or fibroids; instil slowly and check with repeat filling
A normal external fundal contour distinguishes a septate from a bicornuate uterus and matters for management

Structured Report

State the timing in the cycle, contrast used and catheter type
Describe the uterine cavity contour and any filling defects
Report tubal patency on each side and describe any hydrosalpinx or occlusion
Comment on peritoneal spill and any intravasation
Give an impression and recommend pelvic ultrasound or MRI to clarify uterine anomalies

References

ACR-SPR-SRU Practice Parameter for the Performance of Hysterosalpingography
Simpson WL et al. Hysterosalpingography: A Reemerging Study. RadioGraphics
Chalazonitis A et al. Hysterosalpingography: Technique and Applications. Current Problems in Diagnostic Radiology
Royal College of Radiologists iRefer: Making the Best Use of Clinical Radiology

Educational clinical decision support only. Protocols vary by institution and equipment; always confirm with a qualified radiologist and local guidelines before clinical use.

Hysterosalpingography (HSG)

📋 Indications

⛔ Contraindications & Cautions

🧑‍⚕️ Patient Preparation

⚙️ Technique & Parameters

🔎 Systematic Review

🩻 Key Findings & Significance

🧠 Differential Considerations

💡 Pearls & Pitfalls

📝 Structured Report

📚 References