Infertility and Sonohysterography

Quick Answer: Infertility scan: uterus, ovaries, AFC, hydrosalpinx. SHG = saline in cavity for polyps/submucosal fibroids/synechiae. AFC = 2–10 mm follicles both ovaries. Perform SHG early follicular (days 5–10).

Initial Infertility Ultrasound Goals

Baseline transvaginal study before ART or prolonged infertility workup assesses:

1. Uterine cavity contour (2D; SHG/3D if indicated)
2. Müllerian anomalies (septum, bicornuate)
3. Ovarian reserve markers (AFC, ovarian volume)
4. Hydrosalpinx (reduces IVF success)
5. Endometriosis clues (endometrioma, DIE nodules)

Antral Follicle Count (AFC)

Count follicles 2–10 mm in each ovary during early follicular phase (cycle days 2–5 typically).

AFC is not sole determinant—AMH and age paired clinically. Registry may ask what follicle sizes count toward AFC (2–10 mm, not dominant follicle or corpus luteum).

Sonohysterography (SHG) Technique

1. Early follicular cycle days 5–10 after menses ends
2. Negative pregnancy test
3. Transvaginal probe; sterile catheter into cervix
4. Instill warm sterile saline slowly under real-time guidance
5. Image cavity in sagittal and coronal planes

SHG Findings

Worked Scenario: Normal 2D, Abnormal Cavity

Infertility with normal endometrial stripe on standard TV. SHG shows focal filling defect—polyp likely; hysteroscopic polypectomy may improve implantation before IVF.

3D Ultrasound Role

Coronal uterus reconstruction clarifies septate vs bicornuate and septum length. May acquire 3D dataset during SHG for surgical planning.

Follicular Monitoring (Cycle Tracking)

Serial TV measurements of dominant follicle until collapse and corpus luteum formation for timed intercourse or IUI. Dominant follicle mean diameter ~18–24 mm pre-ovulation—document endometrial thickness same day (trilaminar favorable in fertility context).

Ovarian Hyperstimulation Syndrome (OHSS)

Post-ART complication: enlarged multicystic ovaries, ascites, pleural effusions, hemoconcentration risk. Recognize mild vs severe—severe with tense ascites, hydrothorax, oliguria is emergency.

Contraindications to SHG

Active PID, pregnancy, heavy bleeding, known cervical stenosis without preparation plan.

Hydrosalpinx and IVF

Tubal fluid communicates with endometrial cavity—reduces implantation. Surgical treatment (salpingectomy or proximal occlusion) often discussed before IVF—registry asks why hydrosalpinx matters.

Exam Traps

• SHG in luteal phase (pregnancy risk, thick endometium obscures)
• AFC including follicles >10 mm or corpus luteum
• Missing hydrosalpinx on baseline infertility scan
• Septum missed without coronal/SHG view
• Forcing catheter without visualization—perforation risk (gentle technique under guidance)

Infertility imaging is cavity architecture—SHG transforms flat endometrial stripe into diagnosable three-dimensional space for polyps, fibroids, and synechiae.

Ovarian Reserve: Beyond AFC

Antral follicle count complements AMH and age—not standalone. Ovarian volume >10 cc with many small follicles suggests PCOS pattern. Diminished reserve shows low AFC, small ovaries, increased FSH clinically. Registry asks which follicle sizes count in AFC: 2–10 mm, excluding dominant follicle and corpus luteum.

Follicular Monitoring Protocol

Serial TV scans track dominant follicle growth (~1–2 mm/day) until collapse and corpus luteum formation. Endometrial thickness same day: trilaminar pattern favorable pre-ovulation. Document right vs left dominant follicle. Trigger timing for IUI/IVF uses follicle size ≥18 mm per protocol.

Hysterosalpingo-Contrast Sonography (HyCoSy)

HyCoSy evaluates tubal patency with contrast (foam or saline with air) under ultrasound—alternative to HSG. Free spill of contrast around ovary indicates patency. Hydrosalpinx shows dilated tube without spill. Baseline infertility workup may include HyCoSy or HSG after cavity assessment.

SHG Complications and Patient Preparation

Cramping common during saline instillation. Vasovagal response possible—monitor patient. Antibiotic prophylaxis per institutional policy if cervical stenosis or PID history. NSAIDs pre-procedure reduce pain. Document catheter placement and amount of saline instilled.

Uterine Cavity Abnormalities Affecting Implantation

Normal 2D endometrial stripe does not exclude intracavitary lesion—SHG increases polyp detection significantly.

Endometrial Receptivity Imaging (Recognition)

Endometrial thickness alone does not guarantee receptivity. Pattern (trilaminar) and timing relative to ovulation matter in ART. Advanced ERA testing is molecular—not ultrasound—but registry may contrast structural SHG findings with functional receptivity testing conceptually.

Male Factor and Scrotal Ultrasound (Brief)

Infertility workup may include scrotal ultrasound for varicocele—not OB/GYN sonographer primary domain—but registry occasionally references complete infertility imaging pathway including structural uterine and tubal assessment before ART.

HyCoSy Tubal Patency

HyCoSy assesses tubal patency with contrast—free spill indicates patency. AFC counts 2–10 mm follicles bilaterally in early follicular phase—exclude corpus luteum and dominant follicle from count.

SHG Timing and Safety

Perform SHG cycle days 5–10 with negative pregnancy test. Early follicular timing avoids luteal-phase pregnancy risk and optimizes thin endometrium for cavity distension.

Follicular Monitoring Pearls

Dominant follicle ~18–24 mm pre-ovulation; document endometrial thickness same day. OHSS after ART shows enlarged multicystic ovaries, ascites, and pleural effusions—severe cases are emergencies.