Single-Nucleotide Polymorphism–Microarray Ploidy Analysis of Paraffin-Embedded Products of Conception in Recurrent Pregnancy Loss Evaluations

Abstract

II.

Added value of chromosomal microarray analysis over karyotyping in early pregnancy loss: systematic review and meta‐analysis

“…The search identified 630 articles, 29 of which were full-text reviewed and 20 of those were finally included in the meta-analysis 9,[19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37] . Nine studies were excluded either because reported data could not be extracted, or identification of the gestational age or indication for sampling for each case was not provided (if late pregnancy losses or other indications for CMA were included, respectively), or if only morphologically abnormal embryos were included or could not be identified (Table S2).…”

“…The main characteristics of the 23 studies included in the meta-analysis are outlined in Table 1. Ten studies included only first-trimester pregnancy losses 9,20,22,23,25,30,35,37,38,40 and 13 included losses under 20 weeks 19,21,24,[26][27][28][29][31][32][33][34]36,39 . In six studies, CMA was performed after a normal karyotype or QF-PCR result, in seven studies it was performed concurrently to karyotyping, and in the remaining 10 as a first-tier technique.…”

“…Only for cases with normal karyotype was the incremental yield over karyotyping assessed. Seven studies included samples of recurrent pregnancy losses 27,30,[35][36][37][38][39] . Quality assessment of the included studies using QUADAS-2 is shown in Figure 2.…”

“…Funnel plots are provided as online supplementary material (Figures S1 and S2). 38 Warren (2009) 21 Robberecht (2009) 9 Zhang (2009) 22 Gao (2012) 40 Wang (2014) 28 Levy (2014) 26 Lin (2015) 32 38 Warren (2009) 21 Robberecht (2009) 9 Zhang (2009) 22 Rajcan-Separovic (2010) 39 Deshpande (2010) 23 Gao (2012) 40 Li (2013) 24 Wang (2014) 28 Kooper (2014) 25 Levy (2014) 26 Kudesia (2014) 27 Rosenfeld (2015) 31 Romero (2015) 29 Lin (2015) 32 Maslow (2015) 30 Ozawa (2016) 35 Zhang (2016) 33 Wou (2016) 34 Sahoo (2017) 36 Wang (2017) The mean test success rate obtained by karyotyping was 68% (920/1352), while that by CMA was 92% (12 812/13 911) (Table S3). In the nine series reporting concurrent success rates, a 41% increase, accounting for 27 percentage points, was observed, from 68% (920/1352) (95% CI, 66-70%) by karyotyping to 95% (1202/1263) (95% CI, 94-96%) by CMA ( Table 2).…”

Genetic causes of recurrent miscarriages

“…If the fetal tissues are already well formed and visible, a fragment of the umbilical cord may be used for examination purposes. Miscarried material may also be analyzed in paraffin blocks [31]; such examinations may be carried out several years after the block is prepared [32].…”