Congenital uterine anomalies — structured SAQ (15 marks)

(a) Classification systems and the current ASRM standard (3 marks)

One mark per system named with its defining feature.^[1][2]

• AFS 1988: the original American Fertility Society classification — simple and recognisable, and correlated with pregnancy outcomes, but focused on the uterus, excluded vagina and cervix, lacked clear diagnostic criteria, and could not classify complex anomalies.^[1]
• ESHRE/ESGE (CONUTA) 2013: anatomy-based, main classes U0 normal, U1 dysmorphic, U2 septate, U3 bicorporeal, U4 hemi-uterus, U5 aplastic, U6 unclassified; cervical and vaginal anomalies classified independently.^[2]
• ASRM 2021 (MAC2021): the current ASRM standard — built on the 1988 AFS classification but expanded to include the vagina and cervix, with nine descriptive categories.^[3]

(b) Why prevalence varies so widely, and the figures by reproductive-risk group (4 marks)

One mark for the mechanism of variation; up to three marks for the prevalence ladder with figures.^[6]

• Mechanism: the reported prevalence of septate uterus depends on which diagnostic criteria are applied. In the Carriles study of 977 women, ESHRE/ESGE criteria identified septate in 13.5%, ASRM 2021 in 1.4%, and CUME in 2.4% — a near tenfold swing on the same cohort. The Ludwin CUME study found only 2.7% of women met all three definitions.^[6]
• Prevalence ladder (Chan 2011, optimal tests): about 5.5% in the unselected population (95% CI 3.5–8.5), 8.0% in infertile women, 13.3% in those with a history of miscarriage, and 24.5% in women with both miscarriage and infertility.^[5]
• Key qualifier: arcuate uterus is the commonest anomaly in the unselected population (about 3.9%) and is not increased in high-risk groups; septate uterus is the commonest in high-risk groups.^[5]

(c) Diagnostic work-up and the imaging modality (3 marks)

One mark per point, maximum three.^[4]

• First-line: 3D transvaginal ultrasound — recommended by the ESHRE/ESGE Thessaloniki consensus for symptomatic or high-risk women; it renders the coronal plane, showing both the cavity and the external fundal contour.^[4]
• For complex anomalies or diagnostic dilemmas: MRI and endoscopic evaluation; MRI is the ideal modality for complex anomalies and surgical planning.^[4]
• Confirming the external contour: the external fundal contour on the 3D-rendered coronal view is the feature that distinguishes septate (normal contour) from bicornuate (external cleft) — this must be established before any surgery. Add renal tract imaging given the shared embryological origin.^[4]

(d) Surgical management and the quality of the evidence (5 marks)

One mark per point, maximum five.^[7]

• Match the operation to the anomaly: hysteroscopic metroplasty for a septate uterus; abdominal (Strassman) metroplasty for a bicornuate uterus with significant reproductive morbidity; drainage or resection for an obstructive anomaly.^[2]
• Not all anomalies are operated on: arcuate and many asymptomatic anomalies are managed expectantly; the clearest indication for septum resection is recurrent pregnancy loss.^[2]
• Principle of metroplasty: resect the fibrous septum to restore a single, adequately vascularised cavity.^[2]
• Evidence direction: the Wu 2022 systematic review found hysteroscopic resection associated with a higher term-delivery rate (odds ratio 2.26, 95% confidence interval 1.26 to 4.05).^[8]
• Evidence quality and the honest caveat: the Joosse 2025 Cochrane review states the evidence is mainly retrospective and that the major flaw is the before–after design, which always favours the intervention; the definitive randomised trial (TRUST) was still accruing. Counsel the woman on evidence strength, and mention postoperative intrauterine adhesion risk and the need for surveillance of preterm birth and placental complications in future pregnancies.^[7]