The effect of ICSI in infertility couples with non-male factor: a systematic review and meta-analysis

Purpose We performed a systematic review and meta-analysis of available literature to investigate the efficacy of the intracytoplasmic sperm injection (ICSI) in couples with non-male factor with respect to the clinical outcomes. Methods The literature search was based on EMBASE, PubMed, and the Cochrane Library. All studies published after 1992 until February 2020 and written in English addressing patients in the presence of normal semen parameters subjected to ICSI and in vitro fertilization (IVF) were eligible. Reference lists of retrieved articles were hand-searched for additional studies. The primary outcomes were fertilization rate, clinical pregnancy rate, and implantation rate; the secondary outcomes were good-quality embryo rate, miscarriage rate, and live birth rate. Results Four RCTs and twenty-two cohort studies fulfilling the inclusion criteria were included. Collectively, a meta-analysis of the outcomes in RCTs showed that compared to IVF, ICSI has no obvious advantage in fertilization rate (RR = 1.16, 95% CI: 0.83-1.62), clinical pregnancy rate (RR = 1.04, 95% CI: 0.66-1.64), implantation rate (RR = 1.12, 95% CI: 0.67-1.86), and live birth rate (RR = 1.17, 95% CI: 0.43-3.15). Pooled results of cohort studies demonstrated a statistically significant higher fertilization rate (RR = 1.16, 95% CI: 1.03-1.31) and miscarriage rate (RR = 1.04, 95% CI: 1.01-1.06) in the ICSI group; furthermore, higher clinical pregnancy rate (RR = 0.85, 95% CI: 0.77-0.94), implantation rate (RR = 0.78, 95% CI: 0.65-0.95), and live birth rate (RR = 0.86, 95% CI: 0.79-0.94) was founded in the IVF group; no statistically significant difference was observed in good-quality embryo rate (RR = 0.98, 95% CI: 0.93-1.04). Conclusion ICSI has no obvious advantage in patients with normal semen parameters. Enough information is still not available to prove the efficacy of ICSI in couples with non-male factor infertility comparing to IVF.