Definition, prevalence, clinical relevance and treatment of T-shaped uterus: systematic review.

Objectives: To summarize in a systematic review the current evidence regarding definitions, diagnosis, prevalence, etiology, clinical relevance and impact of surgical treatment for T-shaped uterus not related to diethylstilbestrol (DES) exposure, and to highlight areas on which future research should focus.

Methods: A search of PubMed, Scopus and EMBASE was performed on 9 April 2020 using the search terms 't-shaped OR t-shape OR infantile OR (lateral indentation) OR (diethylstilbestrol OR DES) AND (uterus OR uterine OR uteri) AND (anomaly OR anomalies OR malformation OR malformations)'. Additionally, the reference lists of the included studies were searched manually for other relevant publications. All studies presenting data on T-shaped uterus not associated with DES exposure and including at least 10 women were considered eligible. Studies regarding DES-related T-shaped uterus were excluded because DES has not been used since 1971. There were no restrictions on language, date of publication or status of publication.

Results: Of 2504 records identified by the electronic search, 20 studies were included in the systematic review. The majority of studies were of poor quality. In 11 of 16 studies reporting on the diagnosis of T-shaped uterus, the diagnostic method used was three-dimensional ultrasound. There is no consensus on the definition of T-shaped uterus, but the most cited criteria (4/16 studies) were of the European Society of Human Reproduction and Embryology and the European Society for Gynaecological Endoscopy (ESHRE/ESGE; 2013). The prevalence of T-shaped uterus varied from 0.2% to 10% in the four included studies reporting such data. With respect to etiology (except for DES), T-shaped uterus was considered a primary condition in three studies and secondary to adhesions in five and adenomyosis in one. T-shaped uterus was related to worse reproductive outcome based on subfertility (nine studies), miscarriage (seven studies), preterm delivery (two studies), ectopic pregnancy (one study) and repeat implantation failure (seven studies). Of the 12 studies that reported on the effects of surgical treatment of T-shaped uterus by hysteroscopic metroplasty, some mentioned an improvement in pregnancy rate (rates ranging from 49.6% to 88%; eight studies), live-birth rate (rates ranging from 35.1% to 76%; seven studies) and term-delivery rate (four studies) and a reduction in miscarriage (rates ranging from 7% to 49.6%; five studies) and ectopic pregnancy (one study). However, the evidence is of very low quality with serious/critical risk of bias toward overestimating the intervention effect. Some authors reported no complications related to the procedure, while others mentioned persistence of the dysmorphism (rates ranging from 1.4% to 11%; three studies), bleeding (1.3%; one study), infection (2.6%; one study) and adhesions (11.1% and 16.8%; two studies).

Conclusions: The prevalence, etiology and clinical relevance, with respect to reproductive outcome, of T-shaped uterus remain unclear and there is no consensus on the definition and diagnostic method for this condition. Expectant management should be considered the most appropriate choice for everyday practice until randomized controlled trials show a benefit of intervention. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.