Department of Pathology and Laboratory Medicine, Women and Infants Hospital, Alpert Medical School of Brown University, Providence, Rhode Island, USA.
Department of Obstetrics and Gynecology, Cedars-Sinai Medical Center, Los Angeles, California, USA.
Genet Med. 2014 May;16(5):419-22. doi: 10.1038/gim.2013.149. Epub 2013 Oct 3.
We sought to compare measurements of circulating cell-free DNA as well as Down syndrome test results in women with naturally conceived pregnancies with those conceived using assisted reproductive technologies.
Data regarding assisted reproductive technologies were readily available from seven enrollment sites participating in an external clinical validation trial of nested case/control design. Measurements of circulating cell-free fetal and total DNA, fetal fraction (ratio of fetal to total DNA), chromosome-specific z-scores, and karyotype results were available for analysis.
Analyses were restricted to 632 euploid (5.2% assisted reproductive technologies) and 73 Down syndrome (13.7% assisted reproductive technologies), including 16 twin pregnancies. No differences were found for fetal or total circulating cell-free DNA, or for the fetal fraction in euploid (P = 0.70) or Down syndrome (P = 0.58) pregnancies by method of conception. There appeared to be systematic z-score reductions for chromosomes 21, 18, and 13 in assisted reproductive technologies versus natural euploid pregnancies (P = 0.048, 0.0032, and 0.36, respectively).
Assisted reproductive technologies and naturally conceived pregnancies contribute similar levels of circulating cell-free DNA into maternal circulation. Small differences in the z-scores of pregnancies achieved by assisted reproductive technologies were observed and do not appear to be test-related artifacts. However, the findings need confirmation before any consideration of changes to testing and reporting protocols.
我们旨在比较自然受孕和辅助生殖技术受孕女性的循环游离 DNA 测量值以及唐氏综合征检测结果。
在参与巢式病例对照设计外部临床验证试验的七个入组地点，很容易获得有关辅助生殖技术的数据。可进行分析的是循环游离胎儿和总 DNA、胎儿分数（胎儿与总 DNA 的比值）、染色体特异性 z 评分和核型结果的测量值。
分析仅限于 632 例正常二倍体（5.2%的辅助生殖技术）和 73 例唐氏综合征（13.7%的辅助生殖技术），包括 16 例双胞胎妊娠。通过受孕方式，在正常二倍体（P = 0.70）或唐氏综合征（P = 0.58）妊娠中，均未发现胎儿或总循环游离 DNA 或胎儿分数存在差异。与自然受孕的正常二倍体妊娠相比，辅助生殖技术中的染色体 21、18 和 13 的 z 评分似乎存在系统降低（分别为 P = 0.048、0.0032 和 0.36）。
辅助生殖技术和自然受孕都会将相似水平的循环游离 DNA 输送到母体内。在辅助生殖技术妊娠中观察到 z 评分的微小差异，但这些差异似乎与检测无关，而是与技术相关。然而，在考虑修改检测和报告方案之前，需要对这些发现进行进一步确认。
