Sperm DNA fragmentation on the day of fertilisation is not associated with assisted reproductive technique outcome independently of gamete quality.

The evaluation of sperm DNA fragmentation has been postulated as a predictive molecular parameter of the semen fertilising potential, as well as the ability to give rise to a healthy embryo and an ongoing pregnancy. However, there are controversial results due to oocyte quality, the use of different measurement techniques and interpretation criteria. Our objective is to investigate if sperm DNA fragmentation on the day of fertilisation influences fertilisation (IVF) outcome in a prospective double-blind study. Three groups of patients were defined: (i) 68 couples undergoing intracytoplasmic sperm injection (ICSI) due to severe male factor with normal ovarian response (NOR); (ii) 113 couples undergoing conventional in vitro fertilisation (IVF) in our oocyte donation programme due to ovarian failure; and (iii) 150 low ovarian response (LOR) patients undergoing ICSI or IVF. TUNEL assay was performed from an aliquot of each capacitated semen sample to detect DNA fragmentation. There was no relationship between blood serum β-hCG positive test, clinical pregnancy and first trimester miscarriage with DFI levels in NOR ( = 0.41,  = 0.36,  = 0.40), recipient ( = 0.49,  = 0.99 and  = 0.38) and LOR ( = 0.52,  = 0.20,  = 0.64) groups of patients, respectively. Therefore, ART outcomes are not affected by sperm DNA fragmentation independently of gamete quality.