Human uterine vasculature with respect to uterus transplantation: A comprehensive review

Bibliometric analysis and global trends in uterus transplantation

AIM

The purpose of this study was to characterize publication patterns, academic influence, research trends, and the recent developments in uterus transplantation (UTx) across the globe.

METHODS

The Web of Science Core Collection database was searched for documents published from the time the database began to include relevant articles to 15 December 2023. With the use of VOSviewer, Citespace, BICOMB, and Incites, a cross-sectional bibliometric analysis was conducted to extract or calculate the evaluative indexes. Publications were categorized by country, institution, author, journal, highly cited papers, and keywords. The variables were compared in terms of publication and academic influence, which further included citation count, citation impact, Hirsh index, journal impact factor, total link strength, collaboration metrics, and impact relative to the world.

RESULTS

A total of 581 papers concerning UTx were initially identified after retrieval, and 425 documents were included. Of the 41 countries participating in relevant studies, the USA and Sweden were in leading positions in terms of publications, citations, and academic influence. The most versatile institution was the University of Gothenburg, followed by Baylor University. The most productive scholars and journals were Brännström M. and Fertility and Sterility , respectively. Five groups of cutting-edge keywords were identified: venous drainage, donors and donation, women, fertility preservation, and fertility. Topics about surgery, first live birth, risk, and in vitro fertilization remain hot in this field.

CONCLUSIONS

UTx is anticipated to enter a golden era in the coming years. This study provides some guidance concerning the authors involved in promoting UTx research, the current development of UTx, and journals to submit their innovative research. This also helps to reach a comprehensive insight and prospect in the near future. In order to establish recognized standards and benefit more patients who are disturbed by uterine infertility, large-scale and well-designed clinical trials are required.

Uterus transplantation: a rescue technique to save the viability and functionality of the graft after intra-operative outflow thrombosis

Objective

To study a surgical approach to venous vascular thrombosis after uterus transplantation (UTx). Uterus transplantation is the only treatment for uterine factor infertility when conventional therapies are not possible. One of the major limitations of UTx is the high incidence of vascular thrombosis, which in most series reaches approximately 20%.

Design

A case report.

Setting

Hospital.

Patients

We report here a technique used in a 30-year-old woman with congenital absence of the uterus who developed intraoperative thrombosis after a UTx from a brain-dead donor.

Intervention

The UTx was performed by revascularizing the graft through bilateral donor internal iliac vessels (artery and vein) anastomosed end-to-side to the external iliac vessels of the recipient. The superior uterine veins were not anastomosed and were left unreconstructed. An end-to-end graft to the recipient's vaginal anastomosis was performed. After uterus reperfusion, congestion of the organ was noted, and bilateral venous thrombosis of the internal iliac veins of the graft was found. A "Y-shaped" venous jump graft was used to restore venous outflow of the left superior uterine vein and the internal iliac vein of the graft after thrombectomy.

Main Outcome Measures

Viability and functionality of the uterus graft after intraoperative bilateral venous thrombosis.

Results

The postoperative course was uneventful, and this UTx resulted in the delivery of a healthy infant.

Conclusion

To our knowledge, this is the first successful rescue technique used to restore venous outflow and save the viability and functionality of a transplanted uterus. We demonstrated that a transplanted uterus from a deceased donor with a monolateral outflow could succeed in pregnancy and the delivery of a healthy infant.

Gender-affirming hysterectomy in the United States: A comparative outcomes analysis and potential implications for uterine transplantation

PURPOSE

Hysterectomy is a gynecological procedure sometimes performed as part of the gender-affirming process for transgender and gender-expansive patients assigned female at birth. Our goal was to compare surgical outcomes between patients undergoing gender-affirming hysterectomy and patients undergoing hysterectomy for benign menstrual disorders. We then explored the implications of gender-affirming hysterectomy for uterine transplantation.

METHODS

We performed a retrospective cohort study using data from the American College of Surgeons National Surgical Quality Improvement Program database from 2009 through 2018. We identified patients undergoing hysterectomy in the United States based on Current Procedural Terminology code. We used the International Classification of Diseases 9 or 10 codes to identify patients with benign menstrual disorders (non-gender-affirming group) and gender dysphoria (gender-affirming group). We compared patient characteristics and surgical complications.

RESULTS

Of the 40,742 patients that met inclusion criteria, 526 (1.3%) patients were individuals with gender dysphoria. Compared to patients who underwent hysterectomy for benign menstrual disorders, gender-affirming patients were younger, were healthier, had a lower prevalence of diabetes, and were more likely to undergo surgery in the outpatient setting, with shorter time to discharge. Complication rates were similar between groups. Logistic regression controlling for the American Society of Anesthesiology classification determined the difference of return to the operating room was not statistically significant (OR 1.082; 95% CI, 0.56-2.10; p = 0.816).

CONCLUSION

Gender-affirming hysterectomy has a safety profile similar to hysterectomy performed for benign menstrual disorders. Researchers should further explore the possibility of uterus donation among these patients as they may be suitable candidates.

Deceased donor availability for uterus transplantation in Australia

BACKGROUND

Uterus transplantation is an emerging treatment option for uterine factor infertility. Most uterus transplantation research programs use living donors, although this comes with considerable surgical and psychological risks and not all women desiring uterus transplantation will have an available living donor. A deceased donor program eliminates donor risks; however, the availability of deceased uterus donors is currently unknown in Australia.

AIMS

To establish the feasibility of a deceased donor uterus transplantation program in Australia and consider expanded inclusion criteria for this model.

MATERIALS AND METHODS

A retrospective review of the New South Wales (NSW) Organ and Tissue Donation Service database was undertaken to identify potential deceased uterus donors, with comparison to the broad deceased donor inclusion criteria from three international uterus transplantation trials including female, brain-dead, multi-organ donation, no major abdominal surgery, and <60 years of age.

RESULTS

Between January 1, 2018, and December 31, 2022, 648 deceased donors were available in NSW. Of these, 43% (279/648) were female and 67% of the women (187/279) were also multi-organ donors. When the brain-dead donor-only and age criteria (<60 years) were applied, a total of 107 deceased donors met the available criteria for uterus transplantation, with an average of 21 deceased donors per year in NSW.

CONCLUSIONS

There appears to be adequate deceased donor organ availability to establish a deceased uterus transplantation program in NSW, Australia. Should interest in uterus transplantation increase, including criteria such as older and nulliparous donors could increase organ availability for a uterus transplantation program.

Graft Failure after Uterus Transplantation in 16 Recipients: A Review

Uterus transplantation (UTx) is now an alternative to surrogacy and adoption for women with uterine factor infertility to have children; however, there are still unresolved clinical and technical issues. One of these is that the graft failure rate after transplantation is somewhat higher than that of other life-saving organ transplants, which is a critical concern. Herein, we summarize the details of 16 graft failures after UTx with living or deceased donors using the published literature in order to learn from these negative outcomes. To date, the main causes of graft failure are vascular factors (arterial and/or venous thrombosis, atherosclerosis, and poor perfusion). Many recipients with thrombosis develop graft failure within one month of surgery. Therefore, it is necessary to devise a safe and stable surgical technique with higher success rates for further development in the UTx field.

Immunosuppression in uterus transplantation: from transplant to delivery

INTRODUCTION

Uterus transplantation introduces unique challenges regarding immunosuppression, including the effects of immunosuppressive drugs on the fetus and graft rejection during pregnancy. Although immunosuppressive regimens are based on protocols used after solid organ transplantation, in recipients of uterus grafts, the physician must consider therapy modifications based on the phase of the transplant, from the intra-operative period through to delivery.

AREAS COVERED

This review discusses the current immunosuppressive rationale in uterus transplantation, focusing on the therapy in each phase of the transplant. The authors present an overview of the already approved immunosuppressive medications for solid organ transplantation, their application in uterus transplant prior to pregnancy, during pregnancy and as rejection treatment.

EXPERT OPINION

Most medications used for uterus transplant are adopted from solid organ transplantation experience, especially kidney transplantation, and rejection is treated in standard fashion. Research is needed to clarify the drugs' effects on fetal and neonatal well-being and to develop new medications to achieve better tolerance. Early markers of uterus graft rejection need to be identified, and prior rejection episodes should no longer be a cause to remove the graft during delivery in a recipient who wants a further pregnancy.

Radiologic Evaluation of Uterine Vasculature of Uterus Transplant Living Donor Candidates: DUETS Classification

Uterus transplantation is a treatment solution for women suffering from absolute uterine factor infertility. As much as 19.5% of uterus-transplanted patients underwent urgent graft hysterectomy due to thrombosis/hypoperfusion. The necessity to identify candidates with high-quality uterine vasculature is paramount. We retrospectively evaluated and compared the imaging results with actual vascular findings from the back table. In this article, we present a novel radiologic grading scale (DUETS classification) for evaluating both uterine arteries and veins concerning their suitability for uterus procurement and transplantation. This classification defines several criteria for arteries (caliber, tapering, atherosclerosis, tortuosity, segment, take-off, and course) and veins (caliber, tapering, plethora, fenestrations, duplication/multiplicity, dominant route of venous drainage, radiologist’s confidence with imaging and assessment). In conclusion, magnetic resonance angiography can provide reliable information on uterine venous characteristics if performed consistently according to a well-established protocol and assessed by a dedicated radiologist. The caliber of uterine arteries seems to be inversely related to the time passed since the last delivery. We recommend that the radiologist comments on the reliability and confidence of the imaging study. It cannot be over-emphasized that the most crucial aspect of surgical imaging is the necessity of high-quality communication between a surgeon and a radiologist.

Evolution and Transformation of Uterine Transplantation: A Systematic Review of Surgical Techniques and Outcomes

BACKGROUND

 Uterine transplantation (UTx) is acknowledged to be on the second (2A) of five steps of development in accordance with the staging system for the evaluation of surgical innovations. Accordingly, we aimed to systematically review the available evidence of the surgical techniques and outcomes of UTx in terms of graft survival.

METHODS

 A comprehensive search was conducted across PubMed Medline, Cochrane-EBMR, Scopus, Web of Science, and CENTRAL through November 2020.

RESULTS

 Forty studies, reporting 64 recipients and 64 donors, satisfied inclusion criteria. The surgical time and the estimated blood loss were 515 minutes and 679 mL for graft procurement via laparotomy, 210 minutes and 100 mL for laparoscopic-assisted graft harvest, and 660 minutes and 173 mL for robotic-assisted procedures, respectively. Urinary tract infections (n = 8) and injury to the urinary system (n = 6) were the most common donor complications. Using the donor's internal iliac system, two arterial anastomoses were performed in all cases. Venous outflow was accomplished through the uterine veins (UVs) in 13 cases, a combination of the UVs and the ovarian/uteroovarian veins (OVs/UOVs) in 36 cases, and solely through the OVs/UOVs in 13 cases. Ischemia time was 161 and 258 minutes when using living donors (LD) and deceased donors (DD), respectively. Forty-eight uteri were successfully transplanted or fulfilled the purpose of transplantation, 41 from LDs and 7 from DDs. Twenty-five and four live childbirths from LDs and DDs have been reported, respectively.

CONCLUSION

 UTx is still experimental. Further series are required to recommend specific surgical techniques that best yield a successful transplant and reduce complications for donors and recipients.