INTRODUCTION: Expanded genetic carrier testing allows couples to determine their reproductive risk for genetic disorders regardless of an individual's ancestral background or geographic origin. METHODS: As part of routine laboratory management, requisitions were reviewed for information on reproductive partners. Our database was queried for names of reproductive partners, and demographic information was cross-referenced to determine validity of the matched sample. A retrospective analysis was performed for known matched reproductive pairs and descriptive analysis regarding ethnicity, test ordered, and results of genetic carrier testing on each matched pair was performed. RESULTS: Data was entered for 1,585 reproductive partners; after validation and confirmation of carrier testing performed, 783 known reproductive pairs were confirmed. Forty-six (5.9%) couples were found to be at risk for the same autosomal recessive disorder(s), including: hereditary hemochromatosis (20), cystic fibrosis (10), familial Mediterranean fever (6), hemoglobinopathies (5), spinal muscular atrophy (3), primary congenital glaucoma (2), and phenylalanine hydroxylase deficiency (PKU) (1). An additional 1% were potentially at increased risk for the same genetic disorder due to indeterminate results by enzyme analysis or hemoglobin electrophoresis. CONCLUSION: Our study identified 6.9% of couples to be at increased risk to have an affected child, and demonstrates the importance of testing partners to allow for reproductive decision-making. Additionally, 28 (61%) of these couples were found to be carriers of disorders only included on expanded carrier testing panels. Therefore, testing patients with an expanded pan-ethnic panel will identify more couples at risk for disorders that would be missed by current ethnicity-based recommendations.

INTRODUCTION: Expanded carrier testing is recognized by ACOG as an acceptable testing strategy in women’s healthcare. We report a large OB/GYN practice’s experience with expanded carrier testing including partner testing uptake and reproductive risk. METHODS: A retrospective analysis of expanded carrier testing ordered at a multi-provider clinic was performed. Data analyzed included patient demographics, testing outcomes, and reproductive risks. RESULTS: Out of 537 female patients tested, 265 (49.3%) were positive; of those, 201 (75.8%) had partner testing. Fourteen (7.0%) couples were at risk to have a child affected with an autosomal recessive disorder (8 hemochromatosis, 3 familial Mediterranean fever, 1 PKU, 1 primary congenital glaucoma, 1 GJB2 non-syndromic hearing loss). Thirty women were carriers of an X-linked disorder (22 G6PD, 7 Fragile X premutation, and 1 GJB1-related Charcot-Marie Tooth disease). Incidentally, 10 patients were found who may have symptoms of a genetic condition based on their genotype (5 G6PD, 4 hemochromatosis, 1 carnitine palmitoyltransferase II deficiency), which could impact patient and pregnancy management. CONCLUSION: Implementing an expanded carrier testing protocol including partner testing identifies carriers of many disorders and allows for reproductive risk identification. In this cohort, out of 537 patients who were tested, 43 (8.0%) were identified to have reproductive risk either due to an X-linked disorder or as carriers of the same autosomal recessive disorder. Risk identification empowers patients to make informed decisions with the guidance of their provider. This experience demonstrates the yield of expanded carrier testing when routine testing and partner follow-up is incorporated in a busy obstetrical practice.