无细胞胎儿DNA可用于区分整倍体和非整倍体妊娠丢失

丹麦哥本哈根大学医院Henriette Svarre Nielsen团队研究了无细胞胎儿DNA用于遗传评价的可行性。相关论文于2023年2月2日发表在《柳叶刀》杂志上。

四分之一的妊娠以流产告终。尽管对夫妻的影响有充分的文献记载，但缺乏循证治疗和预测模型。胎儿非整倍体与下一次成功妊娠的几率更高，而整倍体妊娠丢失可能归因于潜在的母体疾病。因此倍体诊断是有利的，但具有挑战性，因为它们需要收集妊娠组织。来自母体血液的无细胞胎儿DNA（cffDNA）具有评估胎儿倍体状态的潜力，但尚未对该方法进行大规模验证。

在这项前瞻性队列研究中，作为哥本哈根妊娠丢失（COPL）研究的一部分，丹麦公立医院的三家妇科诊所招募了妊娠丢失妇女。如果年龄大于18岁的女性在怀孕22周（即154天）之前发生了流产，并且通过超声检查确认了宫内妊娠（包括无胚囊），则有资格入选，并且排除了位置不明或葡萄胎妊娠的女性。在妊娠组织仍在原位或妊娠组织消失后24小时内采集母体血液，并通过cffDNA全基因组测序进行分析。妊娠组织的直接测序作为参考。

研究组纳入了2020年11月12日至2022年5月1日，确诊妊娠丢失的连续1000名女性。使用首批333名妊娠丢失妇女（2020年11月12日至2021年8月14日招募）的结果来评估基于cffDNA检测的有效性。来自其他667名女性的结果被纳入以评估cffDNA的表现和结果在1000名女性中的分布。胎儿的胎龄范围为35-149天（平均70.5天，即10周加1天）。

与妊娠组织直接测序相比，基于cffDNA的测试对非整倍体检测的敏感性为85%，特异性为93%。在1000个基于cffDNA的测试结果中，446个（45%）为整倍体，405个（41%）为非整倍体、37个（4%）为多重非整倍体，112个（11%）为不确定结果。333名妇女中有105名（32%）没有收集到妊娠组织，或收集到一份被归类为未知组织的样本。

研究结果表明，对基于cffDNA的妊娠丢失检测的验证表明了区分整倍体和非整倍体妊娠丢失的方法的潜力和可行性，以改善临床管理，并有利于未来的生殖医学和妇女健康研究。

附：英文原文

Title: Cell-free fetal DNA for genetic evaluation in Copenhagen Pregnancy Loss Study (COPL): a prospective cohort study

Author: Tanja Schlaikjr Hartwig, Louise Ambye, Jennifer R Gruhn, Jesper Friis Petersen, Tine Wrnding, Letizia Amato, Andrew Chi-Ho Chan, Boyang Ji, Maiken Hemme Bro-Jrgensen, Lene Werge, Mette Marie Babiel Schmidt Petersen, Clara Brinkmann, Julie Birch Petersen, Morten Dun, Iben Bache, Markus J Herrgrd, Finn Stener Jrgensen, Eva R Hoffmann, Henriette Svarre Nielsen, Henriette Svarre Nielsen, Tanja Schlaikjr Hartwig, Nina la Cour Freiesleben, Finn Stener Jrgensen Jrgensen, Louise Ambye, Sofie Bliddal, Therese Juhlin Sndergaard, Sisse Rye Ostrowski, Erik Srensen, Margit Anita Hrup Larsen, Markus J. Herregrd, Eva Hoffmann, Jenny Gruhn, Andy Chi Ho Chan, Astrid Marie Kolte, David Westergaard, Unnur torsteinsdóttir, Kári Stefánsson, Hákon Jónsson, ólafur t. Magnússon, Valgerdur Steinthorsdottir, Lone Schmidt, Karsten Kristiansen, Pia Rrbk Kamstrup, Mette Nyegaard, Maria Christine Krog, Ellen Christine Leth Lkkegaard, Helle Ejdrup Bredkjr, Charlotte Wilken-Jensen

Issue&Volume: 2023-02-02

Abstract:

Background

One in four pregnancies end in a pregnancy loss. Although the effect on couples is well documented, evidence-based treatments and prediction models are absent. Fetal aneuploidy is associated with a higher chance of a next successful pregnancy compared with euploid pregnancy loss in which underlying maternal conditions might be causal. Ploidy diagnostics are therefore advantageous but challenging as they require collection of the pregnancy tissue. Cell-free fetal DNA (cffDNA) from maternal blood has the potential for evaluation of fetal ploidy status, but no large-scale validation of the method has been done.

Methods

In this prospective cohort study, women with a pregnancy loss were recruited as a part of the Copenhagen Pregnancy Loss (COPL) study from three gynaecological clinics at public hospitals in Denmark. Women were eligible for inclusion if older than 18 years with a pregnancy loss before gestational age 22 weeks (ie, 154 days) and with an intrauterine pregnancy confirmed by ultrasound (including anembryonic sac), and women with pregnancies of unknown location or molar pregnancies were excluded. Maternal blood was collected while pregnancy tissue was still in situ or within 24 h after pregnancy tissue had passed and was analysed by genome-wide sequencing of cffDNA. Direct sequencing of the pregnancy tissue was done as reference.

Findings

We included 1000 consecutive women, at the time of a pregnancy loss diagnosis, between Nov 12, 2020, and May 1, 2022. Results from the first 333 women with a pregnancy loss (recruited between Nov 12, 2020, and Aug 14, 2021) were used to evaluate the validity of cffDNA-based testing. Results from the other 667 women were included to evaluate cffDNA performance and result distribution in a larger cohort of 1000 women in total. Gestational age of fetus ranged from 35–149 days (mean of 70·5 days [SD 16·5], or 10 weeks plus 1 day). The cffDNA-based test had a sensitivity for aneuploidy detection of 85% (95% CI 79–90) and a specificity of 93% (95% CI 88–96) compared with direct sequencing of the pregnancy tissue. Among 1000 cffDNA-based test results, 446 (45%) were euploid, 405 (41%) aneuploid, 37 (4%) had multiple aneuploidies, and 112 (11%) were inconclusive. 105 (32%) of 333 women either did not manage to collect the pregnancy tissue or collected a sample classified as unknown tissue giving a high risk of being maternal.

Interpretation

This validation of cffDNA-based testing in pregnancy loss shows the potential and feasibility of the method to distinguish euploid and aneuploid pregnancy loss for improved clinical management and benefit of future reproductive medicine and women's health research.

DOI: 10.1016/S0140-6736(22)02610-1

Source: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(22)02610-1/fulltext