美国宾夕法尼亚大学佩雷尔曼医学院Courtney A. Schreiber团队研究了人工流产和Rh致敏的风险相关性。这一研究成果于2023年9月26日发表在《美国医学会杂志》上。

虽然人群水平的数据表明，Rh免疫球蛋白在妊娠12周前是非必要的，但临床证据有限。因此，指导方针各不相同，导致Rh检测和治疗的风险和益处混淆。随着传统临床环境中的堕胎治疗变得越来越难，许多人选择自我管理，并需要知道是否有必要进行辅助血型检测。

为了确定在妊娠早期人工流产中，母体接触胎儿红细胞（fRBCs）的频率超过Rh致敏最保守的公布阈值的频率，研究组进行了一项多中心、观察性、前瞻性队列研究，使用高通量流式细胞术检测妊娠早期人工流产（药物或手术）前后配对母体血液样本中的循环fRBCs。参与者包括在妊娠12周0天之前进行妊娠早期人工流产的孕妇。其中506名接受药物（n = 319[63.0%]）或手术（n = 187例[37.0%]）流产。主要结局是在妊娠早期人工流产后，fRBC计数高于致敏阈值（125 fRBC/500万总RBCs）的参与者比例。

在506名参与者中，平均年龄为27.4岁，313名（61.9%）为黑人，123名（24.3%）为白人。506名参与者中有3名在基线时fRBC计数升高；其中1例患者流产后fRBC计数升高（0.2%）。在妊娠早期人工流产后，没有任何参与者的fRBC计数升高超过致敏阈值。与基线相比的中位变化为0 fRBCs，上百分位数分别为24和35.6 fRBCs。尽管流产前和流产后的fRBC计数之间有很强的相关性，但没有其他基线特征与流产后fRBC计数显著相关。

研究结果表明，妊娠早期人工流产不是Rh致敏的危险因素，这表明在妊娠12周之前没有必要进行Rh检测和治疗。这一证据可用于为妊娠早期人工流产后Rh免疫球蛋白给药的国际指南提供信息。

附：英文原文

Title: Induced Abortion and the Risk of Rh Sensitization

Author: Sarah Horvath, Zhen-Yu Huang, Nathanael C. Koelper, Christian Martinez, Patricia Y. Tsao, Ling Zhao, Alisa B. Goldberg, Curtiss Hannum, Mary E. Putt, Eline T. Luning Prak, Courtney A. Schreiber

Issue&Volume: 2023/09/26

Abstract:

Importance  While population-level data suggest Rh immunoglobulin is unnecessary before 12 weeks’ gestation, clinical evidence is limited. Thus, guidelines vary, creating confusion surrounding risks and benefits of Rh testing and treatment. As abortion care in traditional clinical settings becomes harder to access, many people are choosing to self-manage and need to know if ancillary blood type testing is necessary.

Objective  To determine how frequently maternal exposure to fetal red blood cells (fRBCs) exceeds the most conservative published threshold for Rh sensitization in induced first-trimester abortion.

Design, Setting, and Participants  Multicenter, observational, prospective cohort study using high-throughput flow cytometry to detect circulating fRBCs in paired maternal blood samples before and after induced first-trimester abortion (medication or procedural). Individuals undergoing induced first-trimester abortion before 12 weeks 0 days’ gestation were included. Paired blood samples were available from 506 participants who underwent either medical (n=319 [63.0%]) or procedural (n=187 [37.0%]) abortion.

Exposure  Induced first-trimester abortion.

Main Outcomes and Measures  The primary outcome was the proportion of participants with fRBC counts above the sensitization threshold (125 fRBCs/5 million total RBCs) after induced first-trimester abortion.

Results  Among the 506 participants, the mean (SD) age was 27.4 (5.5) years, 313 (61.9%) were Black, and 123 (24.3%) were White. Three of the 506 participants had elevated fRBC counts at baseline; 1 of these patients had an elevated fRBC count following the abortion (0.2% [95% CI, 0%-0.93%]). No other participants had elevated fRBC counts above the sensitization threshold after induced first-trimester abortion. The median change from baseline was 0 fRBCs, with upper 95th and 99th percentiles of 24 and 35.6 fRBCs, respectively. Although there was a strong association between the preabortion and postabortion fRBC counts, no other baseline characteristic was significantly associated with postabortion fRBC count.

Conclusions and Relevance  Induced first-trimester abortion is not a risk factor for Rh sensitization, indicating that Rh testing and treatment are unnecessary before 12 weeks’ gestation. This evidence may be used to inform international guidelines for Rh immunoglobulin administration following first-trimester induced abortion.

DOI: 10.1001/jama.2023.16953

Source: https://jamanetwork.com/journals/jama/fullarticle/2809809