Does sperm origin—Ejaculated or testicular—Affect embryo morphokinetic parameters?

Abstract

Background It is unclear whether sperm origin, either ejaculated or testicular, in couples diagnosed with male factor infertility, affects the timing of the embryo's developmental events evaluated by time‐lapse monitoring and implantation rates. Objective To examine the effect of sperm origin on embryo morphokinetics in couples diagnosed with male factor infertility. Materials and Methods This study included a retrospective analysis of morphokinetic parameters performed by time‐lapse monitoring between 2013 and 2017. The developmental processes and morphokinetic parameters of 419 embryos obtained from couples with male factor infertility attributed to oligo‐astheno‐teratozoospermia, 158 embryos derived from surgically extracted testicular spermatozoa from couples diagnosed with non‐obstructive azoospermia, and 190 embryos from couples with normal ejaculated spermatozoa and female mechanical factor‐related infertility, were evaluated. A comparison of morphokinetic parameters, implantation, and clinical pregnancy rates was performed between the groups with additional analysis in accordance with implantation status. Results Embryos from the normal ejaculated spermatozoa and oligo‐astheno‐teratozoospermia patients reached the later morphokinetic milestones—synchronous division (S3) and time to morula (tM)—faster than embryos obtained from testicular spermatozoa. Implantation rate was similar in the normal ejaculated spermatozoa and oligo‐astheno‐teratozoospermia groups (41.9% vs. 45.8%, NS), with higher implantation rate in the oligo‐astheno‐teratozoospermia group compared to the testicular spermatozoa group (45.8% vs. 33.6%, p = 0.02). Comparison of Known Implantation Data (KID) positive (KIDp) and KID negative (KIDn) embryos in each group revealed more rapid development in KIDp embryos in the normal ejaculated spermatozoa and the oligo‐astheno‐teratozoospermia groups, while in the testicular spermatozoa group implanted embryos reached the late morphokinetic milestones (time to 8 cell stage—t8, ECC3, S3, and tM) significantly faster than embryos that failed to implant. In a multivariate logistic regression analysis of the male factor infertility population, (oligo‐astheno‐teratospermia) (OR = 2.54, p = 0.003) and t8 (OR = 0.95, p = 0.027) were predictive of successful implantation. Male factor infertility embryos that reached the t8 milestone within 48–56 h had favorable implantation rates (p < 0.001). Discussion The study results may highlight another pathophysiology by means of which sperm origin affects embryo developmental kinetics. Selecting embryos demonstrating a faster developmental rate at t8 and specifically the 48‐ to 56 h interval following time of pronuclei fading (tPNf) may improve implantation rates in cases of male factor infertility. Conclusion This study showed that ejaculated spermatozoa is associated with faster late cell divisions, more rapid compaction, and higher implantation rates compared to testicular spermatozoa. Additionally, t8 is an important predictor for implantation in the m...

Time-lapse imaging of human embryos fertilized with testicular sperm reveals an impact on the first embryonic cell cycle

“…Our observation on faster pronuclear appearance is in line with earlier observations [ 36 , 37 ]. Sperm DNA damage needs to be repaired in the oocyte after fertilization [ 22 , 23 ].…”

Nucleation status of Day 2 pre-implantation embryos, acquired by time-lapse imaging during IVF, is associated with live birth

“…Additionally, the impact of normal sperm, impaired ejaculated sperms as well as testicular sperms on early embryo morphokinetics must be considered, especially when the study population is heterogenous, with male and female infertility aetiologies, including azoospermic males where testicular sperms were used to attain fertilization. Differences in morphokinetic parameters on the embryonic cell cycle [ 64 , 65 ], higher aneuploidy rates and mosaicism reported in cases with low sperm concentrations [ 66 ] highlights the need for incorporating sperm origin while developing novel morphokinetic models for embryo selection.…”

Embryological and clinical outcomes in couples with severe male factor infertility versus normozoospermia

“…The study showed that time of pronuclei appearance and fading and the time to cleavage of two cells for embryos from the nonobstructive azoospermia group was slightly more rapid than embryos from the oligoasthenoteratozoospermia group. However, the time of synchronous four blastomere divisions in the third cell cycle and time to morula in the oligoasthenoteratozoospermia group was signi cantly more rapid than those in the nonobstructive azoospermia group [13].…”

“…According to Balaban et al (2001), the use of sperm obtained from the testicles of nonobstructive azoospermia patients reduced blastocyst formation and the implantation rate [12]. Karavani et al (2021) recently compared morphokinetic parameters of embryos between patients with nonobstructive azoospermia versus oligoasthenoteratozoospermia [13]. The study showed that time of pronuclei appearance and fading and the time to cleavage of two cells for embryos from the nonobstructive azoospermia group was slightly more rapid than embryos from the oligoasthenoteratozoospermia group.…”