Analysis of the split insemination (IVF+ICSI) treatment in patients with borderline semen in first cycle

The aim of this study was to verify the effectiveness of the split insemination (IVF+ICSI) in patients with borderline semen for the first cycle, we furthermore compared the treatment outcome of the conventional IVF and ICSI on sibling oocytes with the rate of blastocyst formation in different days (day 5 or day 6) as primary outcome and pregnancy as secondary outcome to provide theoretical support for embryo selection. Between January 2017 and November 2021,190 couples undergoing the split insemination (IVF+ICSI) cycle were enrolled in the study with at least eight oocytes and the borderline semen in first cycle to analyze the basic characteristics and clinical outcome. The remaining 157 patients were analyzed in this study to compare the IVF and ICSI after excluding those who were completely unfertilized by IVF (n=33) including a patient who was completely unfertilized by IVF and ICSI. Present study showed that about 32(32/190,16.8%) patients with borderline semen in first cycle were completely unfertilized performing the conventional IVF and only 1(1/190,0.53%) patient was completely unfertilized using the IVF and ICSI in the split insemination (IVF+ICSI), the rate of total fertilization failure (TFF) was significantly decrease by the ICSI treatment (16.8%&0.53%,P<0.0001). By the split oocytes, the fertilization rate was significantly superior in ICSI(729/982,74.2%) compared to IVF (486/940, 51.7%, P<0.0001), the usable blastocyst and high-quality blastocyst rate on the fifth day were statistically superior in IVF compared to ICSI(31.3% &22.8%,P=0.009) (27.3%&20.6%,P=0.03), The pregnancy rate, implantation rate and live birth rate in the IVF first cycle were higher than the ICSI(75.9%&64%, respectively) (52.3%&41.8%, respectively)(64.8%&54.7%, respectively),although there was no statistical difference,it is also about ten percentage points difference. The treatment of sibling oocyte with both IVF and ICSI could be an appropriate choice to prevent TFF and preserve the embryo development potential for the patients with the borderline semen in present study. Furthermore, the embryo development potential from conventional IVF was better than the embryo from the ICSI technology, the ICSI technology may have a negative effect on the embryo development.