STUDY QUESTION: Does polycystic ovary syndrome influence the morphology of the uterus and the prevalence of congenital uterine anomalies? SUMMARY ANSWER: Available evidence of very low quality shows a possible association between PCOS and some uterine anomalies. WHAT IS KNOWN ALREADY: Congenital uterine malformations range from subtle changes in uterine shapes to major morphologic deformities It is postulated that major anomalies result from the abnormal development of Mullerian ducts. However, the etiology of minor deformities is a subject of speculation. Many factors may impact the development of the uterus and its morphology in utero and after birth. Many researchers have reported on the increased prevalence of uterine anomalies in PCOS patients, yet the synthesis of evidence has not been performed. STUDY DESIGN, SIZE, DURATION: A systematic review and meta-analysis were performed. We systematically searched the PubMed, Scopus, Embase, and Cochrane Library databases using a complex search strategy including terms such as e.g. ‘uterus’, ‘polycystic ovary syndrome’, ‘morphology’, ‘dimensions’, ‘congenital uterine anomalies’, and their synonyms. No language or date restrictions were applied during the literature search. The meta-analysis was based on odds ratio (OR) and 95% CIs using the Mantel–Haenszel random effects model. PARTICIPANTS/MATERIALS, SETTING, METHODS: The primary outcomes included uterine malformations, dimensions, and volume, assessed using non-invasive and invasive methods in observational studies comparing PCOS and non-PCOS patients. We excluded case reports, case series, reviews, studies without control groups, and articles reporting exclusively on polycystic ovary morphology. The modified Newcastle–Ottawa scale was used to assess the quality of the included research. MAIN RESULTS AND THE ROLE OF CHANCE: Our search retrieved 1929 identified publications, 11 of which were included in the systematic review (10 581 women). The majority of the studies were of poor quality. PCOS was associated with higher prevalence of uterine anomalies (OR = 5.96; 95% CI = 1.22–29.17, P = 0.028). The general count of uterine malformations was significantly higher in the PCOS group (25.0%, 95% CI 6.9–43.2, range 0–49%) than in the non-PCOS group (5.3%, 95% CI 0.5–14.8, range 0–23.1%). The studies had a very high heterogeneity. The scope of uterine malformations possibly linked to PCOS included septate, didelphys, I-shaped (morphology that is not recognized by any main classifications), and dysmorphic uteri. The septate uterus was the most often reported malformation. Altered dimensions included fundal indentation depth and angle. Available research used four classification systems: the most frequently reported was that of the American Fertility Society 1988 (3/11). Six studies did not use any classification. The assessment methods included 2- and 3-dimensional ultrasound, magnetic resonance imagining, hysterosalpingography, laparoscopy, and hysteroscopy. LIMITATIONS, REASONS FOR CAUTION: Most of the available studies are of very low quality, use inadequate assessment methods and classifications, and are prone to a high risk of selection bias. Additionally, the differences between PCOS phenotypes and their hormonal aspects are poorly addressed and do not sufficiently explain the etiology of observed changes. The included research displays a varying level of heterogeneity. WIDER IMPLICATIONS OF THE FINDINGS: Further research is needed to (i) confirm whether the association between uterine anomalies and PCOS is clinically relevant, (ii) evaluate whether the prevalence of the uterine anomalies varies between women with different hormonal disturbances (e.g. hyperandrogenism), (iii) assess the benefit of any intervention for uterine anomalies in women with PCOS. STUDY FUNDING/COMPETING INTEREST(S): This study received no funding. The authors have no conflicts to disclose. REGISTRATION NUMBER: CRD42024527964; http://www.crd.york.ac.uk/prospero/

(1) Polycystic ovary syndrome (PCOS) is one of the most common endocrinological disorders worldwide; its complex etiopathology remains poorly understood. PCOS is associated with a broad spectrum of abnormalities, including irregular menses, androgen excess, and increased risk of metabolic, endocrinological, and cardiovascular disorders. This narrative review focuses on structural and functional changes in the uterus associated with polycystic ovary syndrome and hyperandrogenism. (2) The review was performed by searching PubMed, Medline, Embase, Google Scholar, and Cochrane Library electronic databases on records published between 1964 and 2025. The authors included studies on (i) the uterus in clinical settings of PCOS patients, (ii) the uterus in PCOS models, and (iii) the pregnant uterus in patients with PCOS. Multiple animal and human studies describe a potential impact of PCOS on uterine blood flow, morphology, and thickness of the uterine muscle, indicating a possible functional impairment in pregnant and non-pregnant women. The scope of available knowledge regarding functional and structural uterine changes in PCOS is scarce; new studies are warranted. Future research should focus on hyperandrogenism associated with PCOS and explore the link between the morphology and function of the uterus.

Background and Clinical Significance: This study presents a case of a 43-year-old female with a long history of infertility, treated for uterine leiomyoma and endometrial hyperplasia, over a total observation period of 42 months. Case Presentation: Levonorgestrel intrauterine device (LNG-IUD) therapy, as a first and subsequent line of treatment, was introduced. The patient also received medroxyprogesterone acetate oral treatment. Finally, she underwent surgery for an ovarian tumor that appeared to be an ovarian adenocarcinoma concurrent with endometrial cancer. After the removal of the reproductive organ, the patient was diagnosed with synchronous low-grade endometrioid adenocarcinoma in the endometrium and a concurrent grade 2 (G2) endometrioid adenocarcinoma in the left ovary. Conclusions: The prognosis and further management largely depend on whether these are two individual neoplasms or one metastatic tumor. Considering the young age of the patients, an early disease stage, a low grade of both cancers, and favorable prognosis, most synchronous endometrial and ovarian cancers are identified as two independent primary tumors. The diagnosis of a multi-focal neoplasm is important, as in patients with endometrial cancer and ovarian metastasis, the 5-year survival rate is 30–40%, whereas in the case of individual neoplasms, it is 75–80%.