CYSTIC-FIBROSIS GENE-MUTATIONS DO NOT AFFECT SPERM FUNCTION DURING IN-VITRO FERTILIZATION WITH MICROMANIPULATION FOR MEN WITH BILATERAL CONGENITAL ABSENCE OF VAS-DEFERENS

Objective: To assess the effects of cystic fibrosis transmembrane-cond uctance regulator (CFTR) gene mutations on sperm function and fertilit y in men with bilateral congenital absence of the vas deferens. Design : Prospective. Setting: Division of urologic microsurgery and associat ed hospital-based IVF unit. Main Outcome Measures: Fertilization and p regnancy rates. Patients: Men referred to our fertility unit for treat ment of bilateral congenital absence of the vas deferens, using sperm surgically retrieved from the epididymis with IVF and micromanipulatio n. Results: Of 45 men with bilateral congenital absence of the vas, 54 % (19/35) tested were found to be carriers of CFTR gene mutations, wit h one compound heterozygote. Epididymal sperm from men affected with C FTR mutations fertilized 19% (29/152) of oocytes, whereas men without; mutations fertilized 22% (44/204) of oocytes. Pregnancy rates (PRs) w ere 36% (5/14) for cycles involving men with CFTR mutations and 33% (5 /15) for other patients with congenital absence of the vas deferens bu t without detectable CFTR mutations. Conclusions: The presence of dete ctable CFTR mutations does not affect fertilization rates or PRs for m en with bilateral congenital absence of the vas deferens when IVF and micromanipulation are applied.