Department of Surgery, Baylor Annette C. and Harold C. Simmons Transplant Institute, Baylor University Medical Center, Dallas, TX, USA.
Department of Obstetrics and Gynecology, Baylor University Medical Center, Dallas, TX, USA.
Hum Reprod. 2024 Jan 5;39(1):74-82. doi: 10.1093/humrep/dead240.
Do characteristics of the lower uterine segment and cervix modify the risk of preterm delivery in uterus transplant (UTx) recipients?
The cervical length showed little association with preterm delivery, however, cervical inflammation deserves further exploration as a cause of preterm delivery.
UTx recipients do not have the risk factors normally used to stratify pregnancies that would benefit from cervical length assessment. In addition, unique factors related to absent tissues, a different blood supply, inflammatory processes of rejection, cervical biopsies, and a different microbiome challenge the normal progressive remodeling of the cervix and thus cervical competence.
STUDY DESIGN, SIZE, DURATION: This is a subanalysis of a clinical trial of 20 women undergoing uterus transplantation at Baylor University Medical Center from 2016 to 2020, in addition to two women who received transplantation outside of a research protocol at our institution through September 2022. In this report, the first 16 UTx recipients that achieved live birth are included.
PARTICIPANTS/MATERIALS, SETTING, METHODS: The focus of this study was 20 pregnancies that reached the second trimester in 16 women following UTx. We analyzed recipient, transplant, and donor factors to determine if characteristics were associated with delivery outcome. We compared obstetrical outcomes, including planned versus unplanned delivery, by factors such as number of superior venous anastomoses, warm ischemia and cold ischemia times, donor factors including cesarean sections, cervical biopsy results, and cervical ultrasound results.
Planned term deliveries occurred in 44% (8/18) of live births. Of the preterm births, 30% (3/10) were planned and 70% (7/10) were unplanned. Unplanned deliveries occurred in women with spontaneous preterm labor, severe rejection, subchorionic hematoma, and placenta previa. Cervical length in UTx recipients averaged 33.5 mm at 24 weeks and 31.5 mm at 28 weeks, comparable to values from the general population. No relationship was seen between delivery outcome and number of veins used, ischemic time, or number of previous cesarean sections.
LIMITATIONS, REASONS FOR CAUTION: The study's small size allows limited conclusions. The obstetric history of all donors was limited to mode of delivery.
Cervical length measurements in the UTx population are not expected to deviate from those with a native uterus. While cervical length surveillance remains important, attention must be paid to the results of cervical biopsies which are obtained to monitor rejection. Inflammatory processes seem most predictive of preterm delivery.
STUDY FUNDING/COMPETING INTEREST(S): No funding was provided for this study. The authors report no conflicts of interest.
NCT02656550.
下段子宫和宫颈的特征是否会改变子宫移植（UTx）受者早产的风险？
宫颈长度与早产的相关性较小，但宫颈炎症作为早产的原因值得进一步探讨。
UTx 受者没有通常用于分层妊娠的风险因素，这些妊娠受益于宫颈长度评估。此外，与缺失组织、不同的血液供应、排斥反应的炎症过程、宫颈活检和不同的微生物组相关的特有因素挑战了宫颈的正常渐进重塑，从而影响了宫颈功能。
研究设计、规模和持续时间：这是对 2016 年至 2020 年在贝勒大学医学中心接受子宫移植的 20 名女性进行的临床试验的子分析，此外，在我们机构的研究方案之外，还有 2 名女性在 2022 年 9 月前接受了移植。在本报告中，纳入了实现活产的前 16 名 UTx 受者。
参与者/材料、设置和方法：本研究的重点是 16 名接受 UTx 的女性中 20 例妊娠达到中期。我们分析了受者、移植和供者因素，以确定特征是否与分娩结局相关。我们比较了产科结局，包括计划分娩和非计划分娩，比较因素包括上腔静脉吻合术的数量、热缺血和冷缺血时间、供者因素包括剖宫产、宫颈活检结果和宫颈超声结果。
计划足月分娩发生在 18 例活产中的 44%（8/18）。早产中，30%（3/10）为计划性，70%（7/10）为非计划性。非计划性分娩发生在自发性早产、严重排斥、胎盘下血肿和前置胎盘的女性中。UTx 受者的宫颈长度在 24 周时平均为 33.5 毫米，在 28 周时为 31.5 毫米，与一般人群的数值相当。分娩结局与使用的静脉数量、缺血时间或剖宫产次数之间未见相关性。
局限性、谨慎的原因：研究规模小，结论有限。所有供者的产科史仅限于分娩方式。
UTx 人群的宫颈长度测量预计不会偏离具有天然子宫的人群。虽然宫颈长度监测仍然很重要，但必须注意监测排斥反应而获得的宫颈活检结果。炎症过程似乎是预测早产的最主要因素。
研究资金/利益冲突：本研究无资金支持。作者报告无利益冲突。
NCT02656550。
