Effects of Sperm DNA Fragmentation on Embryonic Cleavage and Semen Parameters in In Vitro Fertilization Treatment

Sperm DNA fragmentation (SDF) may influence embryonic development during in vitro fertilization (IVF) treatment. This study examined the relationship between SDF and embryonic development and correlations between SDF and semen parameters.

This retrospective study included couples who received IVF treatment at the Reproductive Medicine Center of Changhua Christian Hospital between July 2020 and May 2022. Couples who experienced repeated implantation failure were suggested to an SDF test, and their most recent IVF treatment results were examined. IVF treatment data were collected for 52 couples. SDF was evaluated using a terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) assay, calculated as 100 × (number of spermatozoa with fragmented DNA/total number of spermatozoa). Couples were divided into two groups on the basis of their SDF ratio: Group 1 (SDF < 20%) and Group 2 (SDF ≥ 20%). The numbers of embryos at the two-pronuclear, cleavage, and blastocyst stages were analyzed using a Chi-square test. Semen parameters were analyzed using a t test.

In all IVF treatment cycles, the fertilization rate was significantly lower in Group 2 than in Group 1 (78.62% vs. 68.88%, p = 0.0378). The cleavage rate was also significantly lower in Group 2 than in Group 1 (57.89% vs. 37.35%, p = 0.0007). The clinical outcome also revealed significantly increased miscarriage rate in Group 2 than in Group 1 (6.25% vs. 14.29%, p ≤ 0.005). Subgroup analysis of young mothers revealed lower fertilization and cleavage rates in Group 2, although the differences were not significant. Analysis of semen parameters revealed significantly lower semen concentrations, sperm motility, and progressive motility in Group 2.

SDF affects early embryonic development. A high SDF ratio is significantly associated with low fertilization and cleavage rates and lower semen concentrations, sperm motility, and progressive motility. The embryo derived from higher SDF ratio sperm also has significantly higher miscarriage rate after embryo transfer. In conclusion, SDF analysis can be used as a useful examination for male fertility before assisted reproductive therapy, especially couples with history of repeat IVF treatment.