Purpose of review: Chromosome microarray (CMA) analysis enables genome interrogation at a much higher resolution than is possible with conventional karyotyping. CMA is considered 'standard of care' for postnatal genetic testing, yet its introduction into the prenatal setting has been delayed, in part because of ethical concerns about possible psychosocial harm and deficits in informed consent.
Recent findings: The findings of several large trials have now been reported, allowing preliminary quantification of the relative benefits and harms of CMA in prenatal diagnosis. Qualitative studies have also provided insights into the patient experience particularly in cases in which results of uncertain significance are provided. In an attempt to minimize potential harms, some professional guidelines have suggested limiting access to CMA to patients with fetal abnormality on ultrasound, limiting the diagnostic power of CMA by using targeted platforms or limiting reporting.
Summary: We provide an overview of the relative benefits and harms of prenatal CMA, and critically examine the strategies proposed to minimize harms in the context of other important ethical issues such as patient autonomy, justice and equity of access. We advocate for improved patient consent, counselling and support so that patients can fully benefit from the improved diagnostic yield of CMA despite the challenges that are intrinsic to the prenatal setting.