Offering pregnant women different levels of genetic information from prenatal chromosome microarray: a prospective

Jane L Halliday1,2, Cecile Muller3,4, Taryn Charles3

  • 1Murdoch Children's Research Institute, Melbourne, VIC, Australia. janehalliday.h@mcri.edu.au.

This study aimed to examine the choice pregnant women make about the amount of fetal genetic information they want from chromosome microarray. Women having invasive prenatal testing in the absence of fetal structural abnormality were recruited in Victoria, Australia. A decision aid for women described 'targeted' analysis as reporting only copy number variants implicated in a highly penetrant and well-described phenotype and 'extended' as additionally reporting variants of uncertain or unknown significance. Participant's choice and demographics were collected by survey before chorionic villus sampling or amniocentesis; psychological data were also collected then and again about 10 days after receiving results. High-resolution single-nucleotide polymorphism array analysis was performed, and a clinical review committee assessed variants for reporting before returning results to participants. Sixty-six participants (59.5%) chose extended analysis and 45 (40.5%) targeted. Choosing extended information was associated with (1) indication for prenatal diagnosis: maternal age alone (adjusted odds ratio (adjOR) 9.6, 95% confidence interval (CI): 1.4-66.0, p= 0.02), or 'other' indication (adjOR 7.1, 95% CI: 1.5-33.1, p= 0.01)); (2) >12 months to conceive (adjOR 4.1, 95% CI: 1.0-17.7, p= 0.05); and (3) Asian background (adjOR 4.67, 95% CI: 1.0-21.0, p= 0.04). No adverse psychological impact occurred in either group. We conclude that offering pregnant women different levels of fetal genetic analysis is warranted, alongside decision support.

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