Genetic study on candidates for oocyte donation.

Objective: There is a rising demand for assisted reproductive medicine, including sperm, oocyte and embryo donation. Besides medical and legal considerations, genetic testing, including carrier screening for multiple autosomal and X-linked recessive disorders plays an essential role in evaluating hereditary risk among donors and therefore exclude them from the donation process.

Methods: A retrospective study was conducted on oocyte donors from a private clinic of assisted reproduction who underwent genetic testing between June 2014 and September 2023. Pre and post-test procedures were performed at the private clinic while karyotyping and carrier screening for Cystic Fibrosis, Fragile X syndrome and Spinal Muscular Atrophy were performed at the Genetic Unit of Faculty of Medicine, University of Porto.

Results: Among 581 donors, 81 women were excluded from the donation process since 5/563 had an alteration in karyotype, 57/581 were carriers of a Cystic Fibrosis Transmembrane conductance Regulator pathogenic variant or had a 5T allele, 11/394 had Survival of Motor Neuron 1 deletion and 8/426 had an intermediate or premutation allele in Fragile X Messenger Ribonucleoprotein gene. While recommendations from fertility societies advocate for comprehensive screening, opinions differ on the mandatory implementation of expanded carrier screening.

Conclusions: In conclusion, the genetic tests and the pre and post-test counseling is imperative to optimize reproductive outcomes in the oocyte donation process.