P-275 Physiological Intracytoplasmic Sperm Injection (PICSI) fails to improve ongoing pregnancy rates: a matched case-control study in advanced maternal age patients

Abstract

Study question Does physiological intracytoplasmic sperm injection (PICSI) using hyaluronic acid binding prior to ICSI improve ongoing pregnancy rate in advanced maternal age patients? Summary answer No differences in ongoing pregnancy rates or miscarriage rates were observed between ICSI and PICSI cycles in patients of advanced maternal age. What is known already Sperm genomic integrity plays a crucial role in the outcomes of intracytoplasmic sperm injection (ICSI), particularly during the post-implantation stage. However, selecting spermatozoa based solely on motility and morphology does not ensure genomic integrity. Hyaluronic acid (HA), a biologically active molecule and a key component of the extracellular matrix surrounding the oocyte-cumulus complex, has been explored as a selection tool for sperm. Recent randomized controlled trials (RCT) investigating the efficacy of HA-based sperm selection prior to ICSI, have demonstrated a reduction in miscarriages after PICSI compared to conventional ICSI (Miller et al., 2019, West R. et al, 2022). Study design, size, duration A retrospective, matched case-control study was conducted between January 2020 and November 2024. A total of 288 cycles were included, 144 PICSI cycles were matched with 144 ICSI cycles. The PICSI group was matched with the ICSI group according to female age, cycle rank, number of injected oocytes and number of previous pregnancies with a 1:1 ratio. Participants/materials, setting, methods The primary outcome was ongoing pregnancy rate after the first transfer, either fresh or frozen-thawed (70 and 35 for ICSI, 66 and 38 for PICSI, respectively). Ongoing pregnancy was defined as a pregnancy showing a positive heartbeat at ultrasound after 12 weeks of gestation. The secondary outcome measures miscarriage rate (defined as pregnancy loss after confirmation of clinical pregnancy). The c2 –test was used to compare categorical variables and Student’s t-test for continuous variables. Main results and the role of chance As a result of matching, the mean female age in both groups was 37.7 ± 4.0, male age was also similar in both groups (39.6 ± 5.3 years vs. 40.2 ± 6.7 years). ). Other baseline characteristics, including cycle rank and mean gravidity showed no significant differences. Sperm parameters such as concentration (49.3 ± 50.3 million/ml in the ICSI group vs. 48.1 ± 39.0 million/ml in PICSI), and progressive motility (18.6% ± 18.2% vs. 18.6% ± 18.6%) showed also no significant differences. Fertilization rates were comparable between ICSI and PICSI group (76.0% vs. 76.1%, p = 1.000), as was the embryo utilization rate (42.0% vs. 41.9%, p = 1.000). In the total, 76 cycles resulted in no transfer due to no fertilization or impaired embryo quality (27.1% (39/144) for ICSI vs 25.7% (37/144) for PICSI, p = 0.894). The ongoing pregnancy rate following the first transfer was 19.1% for the ICSI group and 23.1% for the PICSI group (p = 0.501). The miscarriage rate was also comparable between the two groups (22.8% (8/35) vs. 21.9% (9/41), p = 1.000). The mean number of cryopreserved embryos remaining after the first transfer was similar for both groups (1.74 ± 2.14 vs 1.74 ± 2.81, p = 0994). Limitations, reasons for caution This matched case-control study has limitations due to its retrospective design and small sample size, and although factors such as age and cycle rank were matched, unaccounted confounders may still affect the outcomes. The primary outcome, ongoing pregnancy rate after the first transfer, may not reflect overall reproductive success. Wider implications of the findings The study suggests no significant difference in ongoing pregnancy rates between ICSI- and PICSI-cycles in advanced maternal age patients, questioning the routine use of hyaluronic acid for sperm selection. Trial registration number No