Carrier Screening Insights From a Maternal-Fetal Medicine Practice

Carrier screening is used to determine reproductive risk for autosomal recessive or X-linked conditions, and its clinical implementation varies widely. We evaluated recurring clinical patterns observed at an independent, university-affiliated, high-volume maternal-fetal medicine center in Los Angeles receiving referrals from diverse practice settings. In our view, carrier screening is far too frequently performed later than ideal, which narrows timelines for partner testing, prenatal diagnosis, and decision making and increases patient distress. Carrier screening practices differ by referring clinician, resulting in inequities in detecting genetic risk. Within a single couple, partners are often screened on discordant panels (and sometimes sequentially, maternal-first), which delays risk clarification and increases the chance of misinterpretation. Based on these observations, we believe prepregnancy carrier screening should be prioritized; otherwise, carrier screening should be performed as early as possible in pregnancy with concurrent partner testing. We also believe patients should receive counseling on the benefits and limitations of all available screening options to preserve patient autonomy.