It has been described that 11% of men with semen values within the normal range established by the World Health Organization (WHO) have sperm DNA fragmentation. This has been associated with a lower fertilization rate, lower embryo development and, therefore, lower reproductive success. Focusing on the study of the integrity of the male genome can provide us information to diagnose infertility in the couple. The use of conventional sperm selection methods such as swim-up or density gradients has been a great advance in the improvement of male fertility. However, these methods use centrifugation in their protocol, a procedure that has been associated with sperm DNA damage. The ZyMōt is a chip based on microfluidic properties that allows the recovery of spermatozoa with lower DNA fragmentation rate without centrifugation of the semen sample. This new sperm selection method maintains all the advantages of conventional techniques, but decreasing DNA fragmentation associates to sperm recoveries techniques eventually improving reproductive rates. This quality would be beneficial for patients with unexplained infertility, recurrent pregnancy loss or clinical varicocele, factors that have been associated with a higher index of DNA fragmentation. However up to date there is evidence-based data supporting such improvement. The main objective of the present project is to evaluate the ZyMōt as a new non-invasive sperm selection device and to see its impact on the euploidy rate, comparing it with a sperm selection technique that is routinely used in the clinic: swim-up. At the same time, the effect that this new chip may have on sperm and other reproductive variables will be analyzed clinically, and molecularly with immunohistochemical and transcriptomic analyses in order to observe the impact of SDF(sperm DNA fragmentation) at the molecular and genomic level in oocytes with low reparative potential oocytes.

Inclusion Criteria:

• Couples undergoing an ICSI cycle with PGT-A (Preimplantational Genetic Test for Aneuploidy).
• Males over 18 years of age whose semen sample meets the basic conditions predetermined by the ZyMōt Multi 850µL chip.
• Fresh semen samples.
• Embryos are to be deposited in a time-lapse incubator.
• Women over 37 years of age who have obtained in follicular puncture a number of MII oocytes greater than or equal to 4.

Exclusion Criteria:

• Males with severe asthenozoospermia (<10% progressively motile spermatozoa), globozoospermia (spermatozoa with morphological alterations and lack of acrosome) and/or azoospermia (absence of spermatozoa in the ejaculate).
• Seminal samples obtained by testicular biopsy.
• Samples incubated with calcium ionophore.
• Males and females with previously known abnormal karyotype.
• Oocytes coming from the oocyte donation program.

Embryologists performing IVF/ICSI are blinded to the treatment the sample has undergone. All samples are labeled with the patients Identification number. This is a unique code per patient that does not allow identification of which arm the sample belongs to.