893: Clinical utility of expanded carrier screening: Results-guided actionability and outcomes

Abstract

Expanded carrier screening (ECS) provides couples with information about their risk of having offspring affected by certain genetic conditions. Studies assessing the actions and reproductive outcomes of at-risk couples (ARCs) have been limited. We describe the impact of ECS on planned and actual pregnancy management in the largest sample of ARCs studied to date. Couples who elected ECS and were found to be at high risk of having a pregnancy affected by at least one of 176 genetic conditions were invited to complete a survey about their actions and pregnancy management. Three hundred ninety-one ARCs completed the survey. Of those screened preconceptionally, 77% planned or pursued actions to reduce the risk of having affected offspring, including in vitro fertilization (IVF) with preimplantation genetic testing for monogenic conditions (PGT-M), prenatal diagnostic testing (PNDx), use of donor gametes, adoption, or avoiding pregnancy (Table 1). Of those screened prenatally, 37% elected to undergo prenatal diagnostic testing (PNDx) (Table 1). Approximately one-third of pregnancies were found to be affected, and 42% of affected pregnancies were terminated (Table 1). One hundred sixty-six pregnancies were conceived subsequent to receipt of ECS results; 35% of these pregnancies were achieved through IVF with PGT-M (Table 2). Prenatal diagnosis was pursued in approximately 30% of subsequent pregnancies, with 29% of these pregnancies found to be affected; 75% of affected pregnancies were terminated (Table 2). Declining PNDx was most frequently based on the fear of miscarriage, the belief that termination would not be pursued in the event of a positive result, and the perception that the pregnancy was at low risk of being affected. Planning or pursuing actions appeared to be dependent on the severity of the condition. ECS results impacted couples’ reproductive decision-making and led to altered pregnancy management that reduced the risk of having affected offspring.View Large Image Figure ViewerDownload Hi-res image Download (PPT)