Human uterus transplantation in focus

Three-year follow-up results of two children born from a transplanted uterus

AIMS

To evaluate the 3-year follow-up results of two children delivered at our institution in 2019 from mothers with a transplanted uterus.

METHODS

Observational data on pregnancy outcomes, neonatal course, and growth trajectory in two children born to mothers after uterus transplantation, including 3-year follow-up and neurodevelopmental status assessed using the Bayley Scales of Infant and Toddler Development, third edition (Bayley-III).

RESULTS

Both children were born prematurely via uneventful caesarean sections, to mothers with Mayer-Rokitansky-Küster-Hauser syndrome and a transplanted uterus. An acute caesarean section was performed in one mother because of the onset of regular uterine contractions at 34 weeks and 6 days of pregnancy; in the other mother, an elective caesarean section was performed at 36 weeks and 2 days of gestation. The children were born healthy with no congenital malformations. They had an uneventful postnatal course and showed a normal growth trajectory during 3 years of follow-up. The Bayley-III neurodevelopmental scores of both children were within the normal ranges at ages 2 and 3 years.

CONCLUSION

Though pregnancy after uterus transplantation is associated with the risk of premature delivery, no abnormalities were observed in the neonatal course and 3-year follow-up results, including the neurodevelopmental status, of two children born prematurely to mothers with a transplanted uterus. This is the first report on neurodevelopmental outcomes in children born after uterus transplantation. More data on children born after this radical procedure of uterine factor infertility treatment are required to support our promising results.

[Uterine transplantation, ethical and social aspects]

Uterine transplantation is now a possible treatment for absolute uterine infertility. It is currently proposed to women with Mayer-Rokitansky-Küster-Hauser syndrome but indications will likely to expand in the upcoming years. Despite the progressive standardization of the surgical technique and the reduction in perioperative morbidity for both donors and recipients, the number of transplants performed worldwide remains very low compared to the number of women potentially in need. This is partly due to the singularity of uterine transplantation: the uterus is not a vital organ since one can live without a uterus. It is a temporary transplantation that is not performed to extend life but to improve its quality, responding above all to a desire to conceive and bear a child. Beyond the strictly technical aspect, these particularities raise many ethical questions, both on an individual and social level, which should make us question the real place uterine transplantation should take in our society. Answering these questions will allow us to provide better guidance for future eligible couples and to anticipate ethical problems on the long run.

Analysis of Predictive Factors for Successful Vascular Anastomoses in a Sheep Uterine Transplantation Model

Uterine transplantation is becoming an increasingly realistic therapeutic for uterine infertility. Surgical training on large animal models such as sheep is a prerequisite for establishing a program in humans. The objective of our study was to analyze the predictive factors for successful vascular anastomoses. We performed 40 autotransplants that involved end-to-side anastomoses from the uterine to the external iliac vessels. We analyzed vessel results in terms of success or failure; a total of 78.7% of arterial and 82.9% of venous anastomoses were successful in the immediate postoperative period. In multivariate analysis, independent factors associated with immediate successful vein anastomoses were as follows: a short warm ischemia time (<2 h, OR = 0.05; 95% CI [0.003−0.88], p = 0.04), the absence of any anastomotic complications (OR = 0.06; 95% CI [0.003−0.099], p = 0.049), and their realization by a vascular surgeon (OR = 29.3; 95% CI [1.17−731.9], p = 0.04). Secondly, we showed that an increase in lactate levels greater than 2.72 mmol/L, six hours after reperfusion was predictive of failure, with a sensibility of 85.7% and a specificity of 75.0%. In order to perfect the management of vascular anastomoses by a vascular surgeon, training on animal models and in microsurgery are mandatory in establishing a uterine transplantation program in humans.

Uterine Factor Infertility, a Systematic Review

Uterine factor infertility (UFI) is defined as a condition resulting from either a complete lack of a uterus or a non-functioning uterus due to many causes. The exact prevalence of UFI is currently unknown, while treatments to achieve pregnancy are very limited. To evaluate the prevalence of this condition within its different causes, we carried out a worldwide systematic review on UFI. We performed research on the prevalence of UFI and its various causes throughout the world, according to the PRISMA criteria. A total of 188 studies were included in qualitative synthesis. UFI accounted for 2.1 to 16.7% of the causes of female infertility. We tried to evaluate the proportion of the different causes of UFI: uterine agenesia, hysterectomies, uterine malformations, uterine irradiation, adenomyosis, synechiae and Asherman syndrome, uterine myomas and uterine polyps. However, the data available in countries and studies were highly heterogenous. This present systematic review underlines the lack of a consensual definition of UFI. A national register of patients with UFI based on a consensual definition of Absolute Uterine Factor Infertility and Non-Absolute Uterine Factor Infertility would be helpful for women, whose desire for pregnancy has reached a dead end.

Uterine Transplantation: Recipient Patient Populations

Uterine transplantation is an emerging treatment for patients with uterine factor infertility (UFI). In order to determine patient candidacy for transplant, it is imperative to understand how to identify, counsel and treat uterine transplant recipients. In this article, we focus on patient populations with UFI, whether congenital or acquired, including Mayer-Rokitansky-Kuster-Hauser, complete androgen insensitivity syndrome, hysterectomy, and other causes of nonabsolute UFI. Complete preoperative screening of recipients should be required to assess the candidacy of each individual prior to undergoing this extensive treatment option.

Histopathological examination of the ectocervical biopsy in non-transplanted uteri: A study contributing to the provisional scoring system of subclinical graft rejection after uterus transplantation

INTRODUCTION

Uterus transplantation is a causal treatment for absolute uterine factor infertility. Assessing rejection signs using a histopathological examination of the ectocervical biopsy from the transplanted uterus is common practice in all human uterus transplants worldwide to date. A provisional scoring system was used for the histopathological assessment of subclinical rejection signs in uterus recipients. Here we hypothesized that histopathological and immunohistochemical findings in the normal uteri would differ from the borderline category of subclinical rejection in uterine transplants.

MATERIAL AND METHODS

This prospective observational study included ectocervical biopsies of 54 women who underwent hysterectomy for benign reasons. All biopsy samples were assessed histopathologically and immunohistochemically.

RESULTS

Most of the ectocervical biopsies showed clustering lymphocytic infiltrates affecting the stromal-epithelial interface with the epithelial influx of lymphocytes, primarily CD45RO-positive activated T-cells with CD8 T-lymphocyte predominance. CD4-positive T-lymphocytes and B-cells were rarely detected in the ectocervix. These morphological findings and immunoprofiles of lymphocytic populations overlapped with the so-called borderline changes defined in the provisional scoring system for rejection in the transplanted uteri. The immunoprofiles of ectocervical and endocervical lymphocytic populations differed, with strikingly prominent B-cell participation in the endocervix vs the rare detection of B-cells in the ectocervix.

CONCLUSIONS

The histopathological and immunohistochemical findings in the uteri of premenopausal women were similar to the borderline category of the currently used provisional scoring system of subclinical uterine rejection utilized in all uterine transplant studies. However, future similar studies are required to validate our findings.

Uterus transplantation in a sheep model: novel surgical technique with long-term survival and uterus vitality. First case series in Argentina

OBJECTIVE

To develop a sheep autologous uterus transplantation (UT) program with an innovative surgical technique and assess long term uterus vitality and animal survival.

METHODS

A novel surgical technique consisting of the procurement of the complete uterus and the two ovaries, back table vascular reconstruction, and subsequent implantation in the same animal, performing only two arterial and two venous anastomoses.

RESULTS

Four autologous transplantations were performed; anesthesia and surgery were well tolerated by all the animals without complications. Direct observation and Doppler US performed a week after UT and laparoscopy performed three months later confirmed uterus vitality. All animals were alive more than a year after transplantation.

CONCLUSIONS

Our study was the first to describe a novel surgical technique for sheep uterus autologous transplantation in Latin America, showing long-term survival and uterus vitality.

Immunosuppression in uterine transplantation

Uterine transplantation (UTx) is the only effective treatment for uterine infertility patients to become genetic mothers. After decades of research, the surgical methods of UTx are very developed. There are numerous factors that affect the results of UTx, such as selection of the donor uterus before transplantation, immunosuppressive therapy post-transplantation, rejection monitoring, and immune tolerance. Studies have shown that immune rejection is a crucial factor affecting the survival rate after organ transplantation. Unlike liver or kidney transplantation, the aim of UTx is to obtain a functional uterus that is able to support successful pregnancy and birth of a healthy fetus. Because of the unique purpose of UTx, its immunosuppressive program is relatively specialized. Some immunosuppressive agents can cause perinatal complications, and inducing immune tolerance is necessary to resolve these side effects. Further understanding of the immune mechanism of UTx and the continuous development of new immunosuppressive agents, combined with the application of assisted reproductive technology, will be more conducive to the realization of UTx to breed offspring.

Assisted Reproductive Techniques and Pregnancy Results in Women with Mayer-Rokitansky-Küster-Hauser Syndrome Undergoing Uterus Transplantation: the Czech Experience

STUDY OBJECTIVE

This study aimed to evaluate the reproductive potential of patients with Mayer-Rokitansky-Küster-Hauser syndrome (MRKHS) who were candidates for uterus transplantation (UTx) before inclusion in the experimental trial, and to summarize the existing experience with posttransplantation embryo transfers in functionally successful cases.

DESIGN AND SETTING

A prospective study at a tertiary medical center.

PARTICIPANTS

Ten pre-UTx women with MRKHS and 7 successful UTx cases.

INTERVENTIONS AND MAIN OUTCOME MEASURES

Ovarian stimulations, frozen embryo collection, embryo transfers, and incidence of pregnancy in MRKHS women in the pre- and posttransplantation periods.

RESULTS

The average number of ovarian stimulations to collect the required frozen embryos was 1.9 (1-3). On average, the number of aspirated oocytes was 16.4 (7-38), 12.6 (5-26) oocytes were fertilized, and 7.0 (1-18) embryos were cryopreserved per cycle. To date, the average number of embryo transfers per recipient was 4.9 (3-8), and the embryo transfer/pregnancy rate was 8.8% (3 of 34). Three pregnancies have been achieved to date, including a missed abortion in the 8th week, a birth in the 35th week, and an ongoing pregnancy in the 30th week.

CONCLUSIONS

Despite the small number of UTx cases, our data indicated that women with MRKHS showed a good response to ovarian stimulation and blastocyst formation. Although the procedures for fertilization, cryopreservation, and transfer of the embryos were standardized, the success rate per embryo transfer achieved in the study group has been low to date.

Uterine transplantation and IVF for congenital or acquired uterine factor infertility: A systematic review of safety and efficacy outcomes in the first 52 recipients

Uterine transplantation (UTx) associated with IVF restores fertility in women affected by absolute uterine factor infertility (AUFI). Pregnancies achieved both in women undergoing any solid organ transplantation and following IVF are associated with an increased risk of maternal and neonatal complications. This systematic review evaluated this risk in UTx-IVF treated women focusing on the safety and efficacy features of the treatment. Twenty-two studies and three press releases reporting on 52 UTx-IVF treatments were identified. Regarding the safety of treatment, 38/52 (73,1%) of surgical procedures led to the restoration of uterine function in recipients, 12/52 (23,1%) of recipients experienced post-operative complications requiring hysterectomy, and 2/52 (3,8%) of procedures failed before uterine recipients’ surgery due to intra-operative complications. Regarding the efficacy of treatment, results focused on transplanted patients showing full recovery of organ functioning: 16/38 (42,1%) of patients achieved a pregnancy, including two women who gave births twice. UTx-IVF pregnancies led to 16 deliveries and all new-borns were healthy. Six out of 16 (37,5%) UTx pregnancies faced major complications during gestation. Preterm births occurred in 10/16 (62,5%) UTx deliveries. Our data indicates that the risk of gestational and delivery complications deserves important consideration in AUFI women receiving UTx-IVF treatments. However, these observations are preliminary and need to be revised after larger series of data are published.

Laparoscopic uterine graft procurement and surgical autotransplantation in ovine model

Currently, uterus transplantation (UTx) is a clinical option for infertile women. Over the past three decades, treating benign or malignant gynecological diseases with minimally invasive gynecological surgery has improved, providing significant advantages over conventional open surgery. This study addresses the method used for laparoscopic live-donor ovariohysterectomy and graft harvest from a sheep model. Using a microsurgical practice, ten grafts were autotransplanted after uterine perfusion. End-to-end anastomosis techniques were used to approximate veins and arteries. Follow-ups were carried out 2-months after surgery and postoperative studies included ultrasound scan, diagnostic hysteroscopy, vascular angiography, and exploratory laparoscopy. All transplants were completed without complications. After vascular anastomosis, total reperfusion of the tissue was accomplished in all animals without confirmation of arterial or venous thrombosis. Angiographic explorations did not show any statistically significant dissimilarity in the arterial diameters between the different examination times. 3-months after uterine transplantation all animals underwent assisted reproduction techniques. Patent uterine arteries were observed 4, 8 and 12 months after the transplant. 6-months after transplantation, six sheep (60%) became pregnant with assisted reproduction practices. We noticed an increase in the degree of fibrosis of the cervix samples in non-pregnant animals of the transplant group. Laparoscopic surgery can be an advantageous approach for the uterus retrieval procedure during uterine transplantation. However, larger sample sized reports are needed in order to accomplish validation, standardization and wider use of this route.

Intra- and Postoperative Blood Flow Monitoring in a Sheep Model of Uterus Transplantation

BACKGROUND

The introduction of the opportunity to transplant a viable uterus into women for fulfilling their desire to have a child has awakened high expectations worldwide.

MATERIALS AND METHODS

A sheep model was used to evaluate tools for optimizing measurement of blood flow in uterine transplantation. Intraoperatively, blood flow was measured using unidirectional Doppler and indocyanine green (ICG) fluorescence imaging. Postoperatively, an implantable Doppler probe served as a tool for clinical monitoring the patency of anastomosed vessels.

RESULTS

ICG imaging showed complete vascularization of the uterus before and in short-term evaluation after surgery. The implantable Doppler probe proved to be highly suitable for assessing patency of vessels in a non-invasive way. Results of histology, and real-time polymerase chain reaction demonstrated viability of the transplanted uterus.

CONCLUSION

Different methods to monitor vasculature patency have proven to be advantageous in supporting both surgeons and researchers in ensuring successful implementation of uterine transplantation.

The Interest of Women with Mayer-Rokitansky-Küster-Hauser Syndrome and Laparoscopic Vecchietti Neovagina in Uterus Transplantation

STUDY OBJECTIVE

The goal of this study was to assess a group of women with Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome with surgically created neovaginas in the interest of uterus transplantation (UTx) and to recruit the first group of applicants for a UTx trial.

DESIGN AND SETTING

This was an original prospective study using semistructured interviews.

PARTICIPANTS

A study group of 50 women with MRKH syndrome with Vecchietti neovaginas was recruited via letter of invitation.

INTERVENTIONS AND MAIN OUTCOME MEASURES

Interest of MRKH women in obtaining experimental UTx for the treatment of absolute uterine factor infertility.

RESULTS

A total of 50 women responded via e-mail and 31 (62% [31 of 50] of the study group) expressed serious interest in UTx after complete information about its risks and benefits was provided during the first semistructured interview. They subsequently agreed to participate in additional interviews and further examinations. Because of various reasons, only 9 women were prepared to enter our UTx trial (18% [9 of 50] of the study group). Three recipients/donors were accepted into the living donor arm and 6 into the deceased brain donor arm of the trial.

CONCLUSION

Nearly two-thirds of our MRKH syndrome study group women with surgically created neovaginas were interested in UTx and motivated to undergo this method of absolute uterine factor infertility treatment. Therefore, this group of women might be approached to participate in ongoing and future UTx trials. Future studies of women with MRKH syndrome might confirm or disprove the results of our survey.

Description and evaluation of experimental models for uterine transplantation in pigs

Objective

To evaluate the technique of uterine transplantation and the use of drugs used in the process of immunosuppression.

Methods

We included 12 sows, and immunosuppression was performed with minimal doses of cyclosporine, and cross-match was done to exclude the possibility of blood incompatibility. Hysterectomy was performed in the donor under general anesthesia, with the removal of the aorta and inferior vena cava in monobloc, and anastomosis of these vessels was made in the recipient.

Results

Six experiments were performed, and on the immediate postoperative period, five animals had good reperfusion. However, on the seventh postoperative day, histological analysis showed rejection in five animals.

Conclusion

The experimental model of uterine transplantation is feasible, but monitoring doses of immunosuppressants is pivotal to prevent rejection episodes.

Uterus transplantation: Toward clinical application in Japan

Background

In recent years, uterus transplantation (UTx) has been applied as the treatment for patients with uterine factor infertility worldwide. Thus, the clinical application of UTx in Japan should be considered through both the history of UTx technology development in the world and future prospects.

Methods

Recent information on UTx was collected via a literature survey and the Internet.

Results

Basic research using various animals has been done mainly since 2000. In 2014, the world's first UTx baby was born in Sweden. In total, 24 UTx procedures have been performed at 10 institutes in nine countries and five births were obtained (as of May, 2017). In Japan, the "Project Team for Uterus Transplantation" initiated UTx experiments in 2008 and the "Japan Society for Uterus Transplantation" was organized in March, 2014. In the rest of the world, the "International Society for Uterus Transplantation" was established in January, 2016.

Conclusion

Uterus transplantation is still under development as a reproductive medicine tool and organ transplant procedure. A collaborative system that is not limited by facilities and specialties should strive to build an "all-Japan" team.

Reconstructing Lineage Hierarchies of Mouse Uterus Epithelial Development Using Single-Cell Analysis

The endometrial layer comprises luminal and glandular epithelia that both develop from the same simple layer of fetal uterine epithelium. Mechanisms of uterine epithelial progenitor self-renewal and differentiation are unclear. This study aims to systematically analyze the molecular and cellular mechanisms of uterine epithelial development by single-cell analysis. An integrated set of single-cell transcriptomic data of uterine epithelial progenitors and their differentiated progenies is provided. Additionally the unique molecular signatures of these cells, characterized by sequential upregulation of specific epigenetic and metabolic activities, and activation of unique signaling pathways and transcription factors, were also investigated. Finally a unique subpopulation of early progenitor, as well as differentiated luminal and glandular lineages, were identified. A complex cellular hierarchy of uterine epithelial development was thus delineated. Our study therefore systematically decoded molecular markers and a cellular program of uterine epithelial development that sheds light on uterine developmental biology.

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Single-cell transcriptome of mouse uterine epithelial development is provided

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Epithelial progenitors during early development of uterine epithelia is identified

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Molecular cascades orchestrating uterine epithelial development are dissected

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Cellular hierarchical map of uterine epithelial development is reconstructed

Deceased Donor Uterine Transplantation: Innovation and Adaptation

This commentary endeavors to share our practical experience in developing and implementing the first uterine transplant clinical trial in the United States. Uterine transplant is a promising novel treatment for uterine factor infertility. After reported successful live births after uterine transplant in Sweden, research teams around the world are either embarking on or are considering the development of uterine transplant protocols. Our observations on the applied rather than theoretical aspects of uterine transplantation research in human subjects are detailed in this article. Important among these considerations are composing a broad and experienced multidisciplinary team as well as performing adequate preclinical preparations, including ideally animal studies and practice organ procurements. Ethical preparation is tantamount to clinical preparation for the complexities inherent in uterine transplant, and our suggestions for updating the current ethical criteria for uterine transplant are outlined here. We also describe our perspectives on the strengths and weaknesses of living compared with deceased donor models. Finally, we describe how a strong program can recover and adapt in the face of setbacks to continue a path toward innovation.

Nonobstructive Reproductive Tract Anomalies: A Review of Surgical Management

Müllerian anomalies include a spectrum of anatomic variants of the genital tract arising from abnormal embryologic development, ranging from incomplete resorption of uterine septa to complete vaginal agenesis. Nonobstructive anomalies are often recognized later than obstructive anomalies, because women do not present with pain. However, nonobstructive anomalies frequently have a negative impact on sexual and reproductive health, and careful evaluation and management of these disorders is warranted. This review focuses on the surgical management of nonobstructive Müllerian anomalies.