The effect of human sperm chromatin maturity on ICSI outcomes

Abstract

Because sperm chromatin may play a key role in reproductive success, we verify the associations between sperm chromatin abnormalities, embryo development and the ability to achieve pregnancy. The evaluation of sperm chromatin maturity using aniline blue (AB), chromomycin A3 (CMA3) and toluidine blue (TB) staining were carried out in group of males from infertile couples that underwent ICSI. Low levels of sperm chromatin abnormalities (< 16%) were found in most subjects (> 50%). A higher percentage of TB-positive sperm cells were discovered in the men from couples who achieved ≤ 50% fertilized oocytes compared to men who achieved > 50%. No significant differences were discovered by the applied tests between the men from couples who achieved ≤ 50% and those who achieved > 50% high-quality embryos on the 3rd or 5th day after fertilization, nor between the men from couples who achieved pregnancy and those who failed. The sperm chromatin maturity did not correlate with the ICSI results. However, the ROC analysis revealed a significant predictive value of TB-positive spermatozoa only for fertilization. Therefore, the TB assay can be considered as a useful test for the prediction of fertilization. Our findings suggest that the level of sperm chromatin abnormalities of the examined men was not clinically significant. No found associations between sperm chromatin maturity and embryo development and the ability to achieve pregnancy. We could not exclude the effects of the repairing processes in the fertilized oocyte. The use of complementary tests that verify the status of the sperm chromatin seems justified.

Sperm Has an Impact on Embryonic Development and Clinical Outcomes: A Study of Sibling Oocytes.

“…For example, Gill et al found no associations between the maturity of sperm chromatin and embryonic development or the competence to achieve pregnancy (19). These ndings were in accordance with some other independent studies that also failed to identify correlations between the maturity of sperm chromatin and reproductive success (20)(21)(22)(23)(24)(25).…”

The association between serum vitamin D level and sperm parameters; A pilot study in a subset of Iranian infertile males

“…According to previous research, sperm DNA fragmentation contributes to abnormal chromatin remodeling, apoptosis during sperm maturation and oxidative stress (25)(26)(27). Furthermore, some evidence has indicated that sperm chromatin maturity is associated with fertilization rate; as a result, its evaluation is of great importance in males' fertility assessments (28). The results of the current study showed a negative significant association between vitamin D level in serum with sperm DNA fragmentation and chromatin immaturity.…”

Paternal factors contributing to embryo quality

“…However, several other studies have expressed uncertainty regarding the correlation between the sperm chromatin organization and embryo quality. A recent Polish study [46] failed to give credence to the association between sperm chromatin maturity and embryo development [measured as the number of blastomeres, symmetry, and cytoplasmic fragmentation]. Another study [47] reported that in IVF, the fertilization rate, percentage of cleaved zygotes, and embryos without fragmentation were similar in males with normal and abnormal sperm chromatin, except that sperm samples with both morphological defects and abnormal chromatin, displayed a reduced fertilization rate.…”