Sperm chromatin condensation defects, but neither DNA fragmentation nor aneuploidy, are an independent predictor of clinical pregnancy after intracytoplasmic sperm injection

Abstract

Purpose The impact of sperm DNA damage on intracytoplasmic sperm injection (ICSI) outcomes remains controversial. The purpose of the study was to evaluate the prognostic value of several types of sperm nuclear damage on ICSI clinical pregnancy. Methods Our retrospective study included a total of 132 couples who consulted for male or mixed-factor infertility that benefited from ICSI cycles from January 2006 to December 2015. All infertile males presented at least one conventional semen parameter alteration. Sperm nuclear damage was assessed using the Motile Sperm Organelle Morphological Examination for sperm head relative vacuolar area (RVA), aniline blue staining for chromatin condensation, terminal deoxynucleotidyl transferase dUTP nickend labeling for DNA fragmentation, and fluorescence in situ hybridization for aneuploidy. Results Infertile males who achieved pregnancy after ICSI had fewer chromatin condensation defects than did males who did not achieve any pregnancy (15.8 ± 12.0% vs. 11.4 ± 7.9%, respectively, P = 0.0242), which remained significant in multivariate regression analysis (RR = 0.40 [0.18 to 0.86], P = 0.02). RVA, DNA fragmentation, and aneuploidy were not predictive factors of ICSI outcomes. The pregnancy rate was significantly decreased by number of progressive motile spermatozoa with normal morphology after migration (P = 0.04). In female partners, 17β estradiol of less than 2000 pg/mL on the day of ovulation induction significantly reduced the occurrence of clinical pregnancy (P = 0.04). Conclusion Sperm chromatin condensation defects were more frequently observed in couples with ICSI failure and should be considered a negative predictive factor for the occurrence of clinical pregnancy.

Oxidative Stress Is Associated with Telomere Interaction Impairment and Chromatin Condensation Defects in Spermatozoa of Infertile Males

“…We observed an increase of chromatin condensation defects among infertile males with oligozoospermia, in agreement with previously published data [ 34 , 48 , 49 , 50 ]. Oxidative stress is responsible for defects of chromatin condensation, in sperm or somatic cells.…”

Association among sperm chromatin condensation, sperm DNA fragmentation and 8‐OHdG in seminal plasma and semen parameters in infertile men with oligoasthenoteratozoospermia

“…Histone replacement by positively charged small proteins, protamines, in the sperm nucleus results in a denser and highly condensed sperm chromatin (Ward & Coffey, 1991). Normal condensation of sperm chromatin with histones and protamines is essential in proper sperm function, semen parameters, fertilisation rate and embryo quality after assisted reproduction techniques (ART) (Bichara et al., 2019; Gunes & Esteves, 2020). Sperm chromatin condensation defects make the sperm amenable to oxidative DNA damage (Vorilhon et al., 2018).…”

Human Sperm Morphology as a Marker of Its Nuclear Quality and Epigenetic Pattern

“…As the percentage of sperm-retained histones and the PTMs involved can influence the success of embryo development, it becomes necessary to be able to select the spermatozoa presenting the “best” epigenetic pattern in human assisted reproductive technologies (ART), that is, those which would be linked to the best and safest embryo development. Nowadays, one of the ways of selecting a spermatozoon before injection into the human oocyte is use of high-magnification microscopy with differential interferential contrast (DIC), also called IMSI (intracytoplasmic morphologically selected sperm injection) [ 28 , 29 , 30 , 31 , 32 ]. This technique allows the selection of morphometrically normal spermatozoa without vacuoles and without chromatin granulation, morphological abnormalities related to defects in sperm chromatin condensation [ 28 , 29 , 30 , 31 , 33 ].…”

“…Nowadays, one of the ways of selecting a spermatozoon before injection into the human oocyte is use of high-magnification microscopy with differential interferential contrast (DIC), also called IMSI (intracytoplasmic morphologically selected sperm injection) [ 28 , 29 , 30 , 31 , 32 ]. This technique allows the selection of morphometrically normal spermatozoa without vacuoles and without chromatin granulation, morphological abnormalities related to defects in sperm chromatin condensation [ 28 , 29 , 30 , 31 , 33 ]. The vacuoles were first described as nuclear craters or thumbprints, or DNA-free areas, in connection with no or low condensation of the sperm chromatin [ 29 , 31 , 34 , 35 , 36 ].…”