Outcomes of preimplantation genetic diagnosis in neurofibromatosis type 1

Abstract

Objective To examine the effect of patient and facility level factors on the success of preimplantation genetic diagnosis (PGD) in patients with neurofibromatosis 1 (NF1). Design Retrospective review. Setting Large PGD reference laboratory. Patient(s) All patients with NF1 referred from June 2004 to May 2013. Intervention(s) None. Main Outcome Measure(s) Embryos' NF1 mutation status and live birth rates. Result(s) Seventy-seven couples underwent 156 PGD cycles during the study period. The average maternal age at the time of embryo biopsy was 33.2 years. The majority of embryos had a day 3 single blastomere biopsy without aneuploidy screening. A diagnosis was obtained for 80% of biopsied embryos; 20% of biopsies were nondiagnostic due to technical failures. Diagnosis was more often obtained for embryos of parents with familial disease and for embryos biopsied at centers that referred multiple NF1 cases. Among diagnosed embryos, 483/1,060 (46%) were unaffected by the parental NF1 mutation. Twenty-two (14%) of the 156 cycles had a confirmed live birth; if the observed success rate is applied to cycles with unknown outcomes, 33/156 (21%) cycles are expected to have resulted in live birth. In multivariate logistic regression, having a live birth was significantly associated with having more unaffected embryos available for transfer (odds ratio 1.33 per additional embryo, 95% confidence interval 1.02–1.72). Conclusion(s) Advances in biopsy and diagnostic techniques which increase the number of unaffected embryos identified may improve live birth rates for patients with NF1. Clinicians should counsel patients about their fertility and reproductive options early, with the use of disease-specific data, to set appropriate expectations for the PGD process.