Prenatal genetic testing for cystic fibrosis: a systematic review of clinical effectiveness and an ethics review

Purpose We aimed to assess the clinical value of prenatal testing for cystic fibrosis (CF) and whether ethical considerations would affect endpoint selection. Methods To determine effectiveness, we conducted a systematic literature review whose protocol outlined search strategies across eight databases, study inclusion criteria, and prespecified literature screening, data extraction, and synthesis processes. We conducted a scoping search on ethical considerations. Results The genetic test showed good diagnostic performance. A change in clinical management was observed: termination of pregnancy (TOP) occurred in most cases where two pathogenic variants were identified in a fetus of carrier parents (158/167; 94.6%). The TOP rate was lower in pregnancies where CF was diagnosed after fetal echogenic bowel detection (similar to 65%). TOP and caring for a child with CF were both associated with poor short-term parental psychological outcomes. Ethical analyses indicated that informed decisions should have been the main endpoint, rather than CF-affected births prevented. Conclusion CF testing leads to fewer CF-affected births. It is difficult to assess whether this means the test is valuable, since patients may not value TOP primarily in terms of maternal or fetal health outcomes, psychological or otherwise. The value of testing should arguably be measured in terms of improving patient autonomy rather than health.