Unintended hemihysterectomy due to a unicornuate uterus: clinical lessons and case report

Introduction

Background

A unicornuate uterus with a rudimentary horn is a congenital abnormality of the female reproductive tract (1). Patients with a noncommunicating uterine horn and functional endometrium are at risk for progressive dysmenorrhea, acute and chronic pelvic pain, infertility, tubal ectopic pregnancy, and other complications (2). Surgical removal of the rudimentary horn, typically through laparoscopy or laparotomy, is considered to be the definitive treatment (3).

Rationale and knowledge gap

Despite established protocols for surgical removal, errors can occur due to reliance on size or incomplete preoperative investigations. While there have been reports on the management of rudimentary uterine horns (4-10), no similar cases of surgical errors have been documented. In this case, misidentifying the rudimentary horn was influenced by limitations in imaging and insufficient intraoperative evaluation. This emphasizes the need for improved communication between the surgical team and radiologists, as well as comprehensive preoperative imaging [three-dimensional ultrasound (3D-US) or magnetic resonance imaging (MRI)] to accurately identify uterine anatomy. The surgeon’s intraoperative judgment is also critical as they must carefully assess the findings and distinguish between the rudimentary horn and the healthy uterine body to prevent errors during complex procedures.

Objective

The objective of this study is to present this unusual case, analyze the misstep made by the physician in the management of the unicornuate uterus, and discuss strategies to improve surgical techniques and clinical decision-making to reduce the likelihood of similar errors and enhance patient outcomes. We present this article in accordance with the CARE reporting checklist (available at https://gpm.amegroups.com/article/view/10.21037/gpm-24-45/rc).

Case presentation

All procedures performed in this study were in accordance with the Helsinki Declaration (as revised in 2013) and the study was approved by the Ethics Committee of West China Second University Hospital, and the Institutional Review Board (IRB) number was 2023(220). Written informed consent was obtained from the patient for the publication of this case report and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.

A 24-year-old woman with dysmenorrhea was referred to our institution in May 2022. She was diagnosed with a unicornuate uterus with a functional rudimentary horn and underwent a hemihysterectomy at a local clinic. But 1 year after previous surgery in outside hospital, she still experienced periodic abdominal pain.

When we traced the history, we found that she had menarche in 12 years old and had experienced dysmenorrhea since then. She visited the Gynecological Hospital and Clinics frequently because of pain and oligomenorrhoea. In 2014, she was initially suspected of having Müllerian duct anomalies. She was subsequently diagnosed with didelphic uteri or unicornuate uterus several times. In 2019, she was diagnosed with polycystic ovarian syndrome (PCOS). Oral contraceptive pills helped restore menstruation, but she would rather not because of pain. In January 2021, a doctor from the local clinic diagnosed her with a unicornuate uterus with a noncommunicating functional rudimentary horn. The ultrasound examination revealed a dysplastic uterus with two asymmetrical uterine horns, 4.9 cm × 2.2 cm × 2.9 cm on the left and 4.7 cm × 4.1 cm × 4.0 cm on the right. Renal ultrasound confirmed no agenesis of the kidney or ureter. Long-term pain made the young woman accept the advice of hemihysterectomy of the rudimentary horn. In February 2021, the doctor found two uterine horns in the pelvis during the operation; the left horns were much smaller and broadly attached to the right horns at the lower segment. Left subtotal hysterectomy and fallopian tube resection were performed with the base of the horn deep in the pelvis. Postoperative examination showed no significant change in the left uterine muscle wall, and the endometrium showed hyperplasia.

After the surgery, the pain was not relieved and the patient did not recover despite the repeated use of oral contraceptives such as drospirenone and ethinylestradiol tablets (II) and other hormonal drugs such as dydrogesterone. In December 2021, the patient visited West China Second University Hospital and underwent thorough examination. Transvaginal ultrasound and vaginal examination could not be performed because the patient was virgin. The transabdominal 3D-US showed hematometra of the residual right horn about 6.95 cm × 5.16 cm × 6.06 cm in size, and there seemed to be a sonogram of the cervix on the left with the diameter of 2.24 cm and length of 3.37 cm. It looked like a right uterus, and the left cervix was not connected (Figure 1). Further MRI examinations showed that a uterine structure without cervix can be seen slightly to the right of the pelvic cavity; only the right uterine horn can be seen; the lower part of the uterine body is atresia, the uterine body is obviously dilated and effusion, the cervical position is slightly to the left, no uterine body can be seen at the upper end, and no communication with the above uterine structure. The vaginal structure was visible below, and the vagina was continuous (Figure 2). Our speculation was confirmed, and the local clinic performed the wrong hemihysterectomy. After the examination, we organized a multidisciplinary discussion and communicated with the patient and her family, explaining existing facts and choices in the future. Therefore, we suggest conservative management or surgery. Conservative management refers to a gonadotropin-releasing hormone agonist (GnRH-a); however, it is only used for short-term symptom relief. She can choose surgical removal of the rudimentary horn but will lose reproductive function. Cervicouterine anastomosis was also suggested, but there was no guarantee of normal uterine morphology or complete remission of cyclic abdominal pain. The patient expressed significant anxiety due to her symptoms and deep concern about her fertility. The options provided to her were thoroughly discussed, and her emotional well-being was considered throughout the decision-making process.

Figure 1 Ultrasound image of a rudimentary, noncommunicating, functional uterine horn (left) and residual cervix (right).

Figure 2 MRI depicted a rudimentary, noncommunicating uterine horn (vertical arrows) and residual cervix (horizontal arrows). MRI, magnetic resonance imaging.

In July 2022, the patient returned to West China Second University Hospital and underwent hysterectomy. She cannot afford the high costs of conservative treatment or accept the potential risks and complications of the new surgical technique. During surgery, we found a rudimentary uterus in the right pelvis and an endometriotic cyst on the front wall (Figure 3). A band of fibrous tissue was attached to the rudimentary horn of the pelvic floor. The horn and residual cervix were not connected. Postoperative pathology indicated no remarkable changes in the myometrium, and the endometrium was in the proliferative phase. After the 1-year follow-up, the pain was completely relieved after surgery (timeline shown in Table 1).

Figure 3 The rudimentary uterine horn and endometriotic cyst in the laparoscopy.

Discussion

Key findings

A unicornuate uterus is a congenital abnormality of the female reproductive tract, with an incidence of approximately 0.06% (4). Among women with unicornuate uteri, a cavitated, noncommunicating rudimentary horn is observed in about 20–25% of cases (3). Surgical excision of the cavitated, noncommunicating rudimentary horn is often justified as a means to alleviate dysmenorrhea (4). In our case, the physician mistakenly resected the healthy uterus, mistakenly identifying it as the rudimentary horn due to its smaller size than the rudimentary horn. Upon reviewing the literature, we noted that the rudimentary horn can be enlarged, potentially due to conditions like adenomyosis or hydro-/hematometra (5,6). Thus, we should not assume that a smaller horn is necessarily the rudimentary one. Additionally, it is worth noting that most rudimentary horns are right-sided (54–80%) (3,7), underscoring the need for caution when encountering a left “rudimentary horn” during surgery.

Strengths and limitations

This case emphasizes the importance of accurate preoperative imaging and intraoperative assessment. Strengths of our approach included a thorough literature review and the identification of potential pitfalls in surgical management. However, limitations exist, particularly the retrospective nature of the analysis and reliance on previously published data, which may not fully capture the complexities of individual cases.

In West China Second University Hospital, the process of determining surgical indications is carefully structured to ensure a thorough evaluation and to reduce the risk of unnecessary or inappropriate interventions. Multidisciplinary discussion: for complex cases such as this one, a multidisciplinary team, including gynecologists, radiologists, surgeons, and sometimes reproductive specialists, convenes to ensure that all perspectives are considered when determining the surgical plan. Preoperative imaging evaluation: emphasis is placed on 3D-US and MRI to assess uterine anatomy. Results are reviewed by both the surgeon and radiologist, with additional tests conducted if necessary. Expert consultation: for uncertain or challenging cases, we seek expert opinions from experienced colleagues or external specialists. Patient discussion: we ensure the patient is involved in decision-making, providing a clear understanding of risks and benefits.

One potential limitation of this case was the patient’s final decision, influenced by both medical factors and the patient’s preferences, leading to the eventual total hysterectomy. Moving forward, we aim to explore options like cervicouterine anastomosis to preserve reproductive potential, considering both patient preferences and case-specific challenges.

Comparison with similar researches

Comparative studies have shown that effective preoperative imaging, such as ultrasound and MRI, can significantly enhance surgical outcomes by clearly delineating the anatomy of the uterine horn and its relationship to the unicornuate uterus (7). For patients presenting with amenorrhea, cyclic pain, or persistent pain, pelvic ultrasound is recommended as the first-line diagnostic approach. Compared to two-dimensional ultrasound (2D-US), 3D-US provides more detailed information about uterine morphology, offering clear visualization of the uterine cavity and the external profile of the uterine fundus. This enables more reliable identification of genital anomalies, such as the rudimentary horn, which is crucial for preoperative planning (8). For patients with unclear or suspicious diagnoses on conventional ultrasound, or those suspected of having vaginal proximal atresia, vaginal septum, cervical atresia, type II unicornuate uterus, or complex reproductive tract anomalies, pelvic MRI examination is recommended (7,8). MRI is more effective for differentiating the presence of uterine rudimentary horns, endometrial tissue, cervix, proximal vagina, and the location of hematometra. Our findings align with existing literature, which emphasizes the need for comprehensive imaging prior to surgery to prevent misidentification of anatomical structures. Besides, we can explore the uterine cavity with a probe through the vagina and cervix to confirm a unicornuate uterus, or we can use a methylene blue test (if the patient had sexual life before). Draining old blood from the suspected rudimentary horn with a wide-bore needle can also make help. How about the cervicouterine anastomosis of the remaining uterine body and cervix? To the best of our knowledge, while there are few successful cases of cervicouterine anastomosis documented (9,10), of which the indication was agenesis of the uterine isthmus, challenges remain, especially considering the anatomical alterations that occur during surgery. The approaches included laparotomy/laparoscopy/robot-assisted laparoscopy. There were no severe complications, except in one case, and the anastomosis site did not allow a probe to pass during the second-look surgery (the patient had regular menstrual periods and no abdominal pain). However, in our case, there were many uncertain factors: (I) the uterus body was located on the right, but the residual cervix was on the left of the pelvis. From our imaging data, we could see those two organs are far apart. The tension must be considered. (II) To what extent was the cervix removed during the last surgery? If there remained sufficient tissue for anastomosis? (III) The original anatomical structure has been destroyed, and postoperative adhesion formation and infection make it even more difficult to accomplish the procedure. If the patient chooses anastomosis, it will be a massive challenge.

Explanations of findings

The findings suggest that preoperative assessments are crucial in differentiating between the healthy uterine body and the rudimentary horn. The literature indicates that conditions like adenomyosis can lead to an enlarged rudimentary horn, which may complicate surgical decision-making. Thus, relying solely on size for identification is inadequate.

Implications and actions needed

The implications of this case are significant, particularly regarding surgical training and patient management. This case prompted a multidisciplinary discussion within our institution, involving gynecologists, radiologists, and surgeons. To mitigate the risk of similar errors, we recommend the implementation of standardized protocols that include comprehensive imaging, exploration of the uterine cavity via probes, and potential drainage of old blood from the suspected rudimentary horn. It is essential to meticulously define anatomy both preoperatively and intraoperatively to ensure the feasibility of reconstructive procedures. Regrettably, this young woman has permanently lost her reproductive function, underscoring the critical need for thorough evaluations of pelvic organs before and during laparoscopic interventions. Medical professionals must approach such cases with patience and a strong sense of responsibility. Additionally, information on subsequent quality improvements or case discussions within the clinic would be an exemplary example of institutional learning.

From the patient’s perspective, a thorough examination of the psychological and reproductive consequences would underscore the relevance of holistic care, as the patient may experience feelings of anxiety or depression due to the permanent loss of reproductive potential. Thus, there should be greater attention to the reproductive consequences of such procedures. Physicians must ensure that patients are well-informed about their diagnosis and the potential surgical options, and that they have an active role in the decision-making process. Providing a detailed description of the findings and expected outcomes will not only empower patients but also help improve the physician’s own diagnostic expertise. This collaborative approach can improve patient satisfaction, promote better psychological outcomes, and ultimately lead to more informed, patient-centered care.

Conclusions

This case highlights the complexities and challenges associated with managing a unicornuate uterus with a rudimentary horn, illustrating the potential for surgical errors due to misidentification of anatomical structures. It emphasizes the necessity of thorough preoperative imaging and careful intraoperative assessments to prevent complications and safeguard patient outcomes. Future research should aim to refine techniques and establish standardized protocols to minimize the risk of similar errors in clinical practice.

Acknowledgments

We would like to extend our greatest thanks to this female patient for trusting her care with us and allowing us to share her story.

Footnote

Reporting Checklist: The authors have completed the CARE reporting checklist. Available at https://gpm.amegroups.com/article/view/10.21037/gpm-24-45/rc

Peer Review File: Available at https://gpm.amegroups.com/article/view/10.21037/gpm-24-45/prf

Funding: None.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://gpm.amegroups.com/article/view/10.21037/gpm-24-45/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All procedures performed in this study were in accordance with the Helsinki Declaration (as revised in 2013) and the study was approved by the Ethics Committee of West China Second University Hospital, and the Institutional Review Board (IRB) number was 2023(220). Written informed consent was obtained from the patient for the publication of this case report and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Liu MM. Unicornuate uterus with rudimentary horn. Int J Gynaecol Obstet 1994;44:149-53. [PubMed]
2. Lin CY, Chen CP, Lin HH, et al. Acute abdomen caused by hematometra and hematosalpinx four months following right oophorectomy in a teenager with right peritubal adhesions, unicornuate uterus and a right noncommunicating rudimentary horn. Taiwan J Obstet Gynecol 2007;46:456-9. [Crossref] [PubMed]
3. Fedele L, Bianchi S, Zanconato G, et al. Laparoscopic removal of the cavitated noncommunicating rudimentary uterine horn: surgical aspects in 10 cases. Fertil Steril 2005;83:432-6. [Crossref] [PubMed]
4. Raga F, Bauset C, Remohi J, et al. Reproductive impact of congenital Müllerian anomalies. Hum Reprod 1997;12:2277-81. [Crossref] [PubMed]
5. von Eye Corleta H, Villodre LC, Reis R, et al. Conservative treatment for a noncommunicating rudimentary uterine horn. Acta Obstet Gynecol Scand 2001;80:668. [Crossref] [PubMed]
6. Devine K, McCluskey T, Henne M, et al. Is magnetic resonance imaging sufficient to diagnose rudimentary uterine horn? A case report and review of the literature. J Minim Invasive Gynecol 2013;20:533-6. [Crossref] [PubMed]
7. Abboud K, Giannini A, D'Oria O, et al. Laparoscopic Management of Rudimentary Uterine Horns in Patients with Unicornuate Uterus: A Systematic Review. Gynecol Obstet Invest 2023;88:1-10. [Crossref] [PubMed]
8. Grimbizis GF, Gordts S, Di Spiezio Sardo A, et al. The ESHRE-ESGE consensus on the classification of female genital tract congenital anomalies. Gynecol Surg 2013;10:199-212. [Crossref] [PubMed]
9. Yang LD, Zhang C, Yang L, et al. Congenital Atresia of Uterine Isthmus: Successful Diagnosis and End-To-End Anastomosis. J Pediatr Adolesc Gynecol 2015;28:e113-7. [Crossref] [PubMed]
10. Richards A, Phy JL, Huang JC. Primary cervico-uterine anastomosis in a patient with agenesis of the uterine isthmus: A case report and review. J Obstet Gynaecol Res 2018;44:2199-203. [Crossref] [PubMed]