Fabrizzio Horta, Javier Crosby, Antonio Mackenna and Christian Huidobro
Sperm DNA fragmentation can have negative consequences in clinical outcomes of couples undergoing Assisted Reproductive Technologies (ART). Sperm separation techniques are an important step in sperm selection for ART. The Magnetic Activated Cell Sorting (MACS) is a novel method that separates sperm by density gradient and molecular filtration to remove apoptotic sperm, which is associated to DNA damage. A decrease of DNA sperm fragmentation could improve ART outcomes. The main aim of this study was to assess the effect of MACS on fertilization, embryo development, implantation, clinical pregnancy and miscarriage rates, in couples undergoing intra cytoplasmic sperm injection (ICSI). Semen samples from 284 patients were divided in two groups; study group (n63) and control group (n = 221), analyzed by embryo transfer day (Day 3: ETD3 and day 5: ETD5) and male factor patients. Density gradients followed by MACS were used as sperm preparation method in the study group, while Swim up was the method used in the control group. Similar results were obtained between both groups for all parameters: fertilization rate of 77.18% versus 75.28%; blastulation rate of 46.66% versus 48.69%; implantation rate of 40.35% versus 35.52%; clinical pregnancy rate of 61.81% versus 59.31% and miscarriage rate of 2.94% versus 7.37%. However, statistical significant differences were found for implantation rate (study group 55.0% and control group 35.43%, p = 0.0138) in day 5 embryo transfers (ETD5). MACS technology does not improve general outcomes; however, it showed better results for ETD5. Further studies are required to identify real improvements in extended embryo culture in male infertility.