P-012 Euploid and good-quality blastocysts using testicular sperm from men with high sperm DNA fragmentation (SDF), oligozoospermia, and previous failed ICSI with ejaculated sperm
Authors: Hervas I , Martinez-Soto J  C , Mollá M , Landeras J , Nicolás M , Fernandez-Olmedilla L , Trabalón M , Rivera-Egea R , Gil Julia M , Garrido N 
Published: July 2024

Study question

Are euploid rate and blastocyst quality improved when testicular sperm is used in patients with elevated SDF and poor semen parameters or/and previous ICSI failure?

Summary answer

The use of testicular spermatozoa in non-azoospermic males does preserve blastocyst ploidy while favoring the proportion of good-quality embryos available for the couple.

What is known already

Sperm extracted from the testicle has been proposed as a strategy to improve reproductive outcomes in couples with elevated DNA fragmentation in the ejaculate and with severe male infertility or previous ICSI failure. Different studies and meta-analyses show to increase pregnancy and live birth rates, and one of the reasons could be the lower genetic damage of spermatozoa retrieved from the testicle. However, there is little information on the effect on the quality of the embryos generated and their ploidy since the use of testicular sperm tends to have a higher rate of aneuploidy.

Study design, size, duration

This is a prospective, blinded, randomized, and controlled trial conducted in a private university-affiliated IVF center between October 2020 and June 2023. In each patient (n = 6), oocytes were randomly microinjected by sperm from the testis (T-ICSI) or ejaculate (E-ICSI) assigned in a 1:1 ratio. All males had an SDF&gt;30% (measured by Sperm Chromatin dispersion (SCD) test), severe oligozoospermia, and/or a previous ICSI failure.

Participants/materials, setting, methods

Males underwent testicular sperm extraction (TESE) to obtain spermatozoa, which were frozen along with an ejaculated semen sample obtained previously on the same day. Women were &lt;38 years old with good ovarian reserve (antral follicle count&gt;10). SDF level was compared between both sources. The primary outcome was the euploid rate (among a total number of biopsied embryos). Secondary outcomes were fertilization rate, blastocyst rate, good-quality blastocyst rate, and ongoing pregnancy rate per embryo transfer (ET).

Main results and the role of chance

Mean ejaculated SDF was 44.83±16.6 (IC95% 27.5 -62.2), while mean women age was 31.8±2.9 (28.76-34.9). An average of 14.5±5.8 metaphase II oocytes were microinjected per patient. A total of 87 oocytes were randomized to the T-ICSI group (n = 45) or E-ICSI group (n = 42). There was a 14% difference between the SDF of testicular (44.7% (31.3-58.0) and ejaculated sperm (58.5% (37.6-79.4) (p = 0.2). The fertilization rate was slightly lower in the T-ICSI group (53.3% (38.1-68.1) compared to the E-ICSI group (61.9 (61.8-76.0) (p = 0.6). A total of 21 embryos reached the blastocyst stage, being the blastocyst arrival rate per correctly fertilized oocyte 41.7% (10/24) (22.8-63.1) for T-ICSI and 42.3% (11/26) (24.0-62.8) for E-ICSI (p = 1.0). Of them, a higher proportion of good-quality blastocysts was found in the T-ICSI (29.2% (13.4-51.6)) group than in the E-ICSI (19.2% (7.3-40.0)) group, although the difference was not statistically significant. In addition, the euploidy rate was comparable between the T-ICSI (60% (27.4-86.3)) and E-ICSI (63.6% (31.6-87.6)) groups (p = 1.0). Seven embryos were transferred in 6 ET, three in each study group. Only one of the ET in the E-ICSI group resulted in pregnancy (33.3% (1.8-87.5), while the three transfers in the T-ICSI group resulted in an ongoing pregnancy (100% (31.0-100)) (p = 1.0).

Limitations, reasons for caution

Despite being a randomized controlled trial, the number of subjects recruited is small; it is necessary to increase the number of cases to obtain results with greater statistical power. TESE is a technique that is not risk-free, so its performance should be evaluated in terms of its cost-benefit for patients.

Wider implications of the findings

The use of less genome-damaged testicular spermatozoa in non-azoospermic males seems to be a reliable strategy for couples with high ejaculated SDF and severe oligospermia and/or previous ICSI failures. However, although we have found an improvement, remains to be statistically confirmed with more cases.

Trial registration number

NCT04795440