The influence of sperm chromatin fragmentation on in vitro fertilization Ana Carolina Fuzete Ibarra, Daniel Siquieroli Vilas Boas

Abstract

 This study evaluated the DNA Fragmentation Index of spermatozoa before and after seminal processing and correlated it with fertilization, cleavage, and pregnancy rates in couples undergoing assisted reproduction cycles using the Intracytoplasmic Sperm Injection (ICSI) technique. Samples used in ICSI were processed using the discontinuous gradient centrifugation method for fertilization. After ICSI, pre- and post-processed samples were analyzed for chromatin integrity, morphology, maturity, and correlated with fertilization, cleavage, and pregnancy rates. Values were expressed as percentages, and statistical analysis was performed using ANOVA. Eleven cycles of ICSI were analyzed, revealing a 54.54% occurrence of biochemical pregnancy and 45.46% pregnancies that progressed beyond the first trimester with one abortion. Processed samples showed a higher number of spermatozoa with fragmented chromatin compared to fresh samples, but with decreased immature spermatozoa indices after seminal processing (p=0.0422). Morphology averages were 4.0% for oval forms in couples who conceived and 3.2% in couples with implantation failures. Chromatin fragmentation averages were 37.1% in couples who conceived and 36.2% in couples with implantation failures. Post-processing recovered immaturity averages were 2.4% in couples who conceived and 5.6% in couples with implantation failures. The discontinuous gradient seminal processing method should be approached cautiously and applied on a case-by-case basis. Implantation failure may be correlated not only with DNA fragmentation rates but also with the degree of spermatozoa maturity.