Receiving uncertain results from prenatal chromosomal microarray analysis: Women's decisions on continuation or termination of pregnancy

Perinatal outcomes after a prenatal diagnosis of a fetal copy number variant: a retrospective population-based cohort study

BACKGROUND

There are no established guidelines for the follow up of infants born after a prenatal diagnosis of a genomic copy number variant (CNV), despite their increased risk of developmental issues. The aims of this study were (i) to determine the perinatal outcomes of fetuses diagnosed with and without a CNV, and (ii) to establish a population-based paediatric cohort for long term developmental follow up.

METHODS

An Australian state-wide research database was screened for pregnant individuals who had a prenatal chromosomal microarray (CMA) between 2013-2019 inclusive. Following linkage to laboratory records and clinical referrer details, hospital records were manually reviewed for study eligibility. Eligible participants were mother-child pairs where the pregnancy resulted in a livebirth, the mother was able to provide informed consent in English (did not require a translator) and the mother was the primary caregiver for the child at hospital discharge after birth. Research invitations were sent by registered post at an average of six years after the prenatal diagnostic test. Statistical analysis was performed in Stata17.

RESULTS

Of 1832 prenatal records examined, 1364 (74.5%) mother-child pairs were eligible for recruitment into the follow up cohort. Of the 468 ineligible, 282 (60.3%) had 'no live pregnancy outcome' (209 terminations of pregnancy (TOP) and 73 miscarriages, stillbirths, and infant deaths), 157 (33.5%) required a translator, and 29 (6.2%) were excluded for other reasons. TOP rates varied by the type of fetal CNV detected: 49.3% (109/221) for pathogenic CNVs, 18.2% (58/319) for variants of uncertain significance and 3.3% (42/1292) where no clinically significant CNV was reported on CMA. Almost 77% of invitation letters were successfully delivered (1047/1364), and the subsequent participation rate in the follow up cohort was 19.2% (201/1047).

CONCLUSIONS

This study provides Australia's first population-based data on perinatal outcomes following prenatal diagnostic testing with CMA. The relatively high rates of pregnancy loss for those with a prenatal diagnosis of a CNV presented a challenge for establishing a paediatric cohort to examine long term outcomes. Recruiting a mother-child cohort via prenatal ascertainment is a complex and resource-intensive process, but an important step in understanding the impact of a CNV diagnosis in pregnancy and beyond.

TRIAL REGISTRATION

ACTRN12620000446965p; Registered on April 6, 2020.

Women's attitudes towards disclosure of genetic information in pregnancy with varying levels of penetrance

BACKGROUND

Chromosomal-microarray-analysis (CMA) may reveal susceptibility-loci (SL) of varied penetrance for autism-spectrum-disorder (ASD) and other neurodevelopmental conditions. Attitudes of women/parents to disclosure of SL during pregnancy are understudied.

METHODS

A multiple-choice questionnaire was distributed to postpartum women. Data were collected on women's interest to receive prenatal genetic information with various levels of penetrance.

RESULTS

Women's (n = 941) disclosure choices were dependent on the magnitude of risk: approximately 70% supported disclosure of either full or 40% penetrance, 53% supported disclosure at a 20% risk threshold, and 40% supported disclosure at 10% or less. Although most women supported, rejected or were indecisive about disclosure consistently across all risk levels, nearly one-quarter (24%) varied their responses based on penetrance, and this was associated with religiosity, education, parity and concern about fetal health (p-values <0.04). Among those who varied their choices, the risk threshold was lower among secular women (20%) than among ultraorthodox women (40%). In a multivariable analysis, ultraorthodox women were much less likely to vary their choices on ASD disclosure compared with secular women (aOR = 0.37, p < 0.001).

CONCLUSION

Women's attitudes toward disclosure are influenced by the level of risk and their individual characteristics. We therefore encourage engaging women/couples in disclosure decisions regarding uncertain and probabilistic results from prenatal genomic tests.