ICSI shows no advantage over conventional IVF in patients with unexpected low oocyte yield

A yield of fewer than five oocytes is associated with a sharp drop in success rates, making each oocyte extremely valuable and demanding highly efficient utilization. Therefore, we aimed to explore the optimal fertilization method for these patients.

This retrospective cohort single-center study included 424 C-IVF cycles and 90 ICSI cycles from 2016 to 2023. All patients were in their first ART cycle, with 3 or 4 oocytes retrieved. The study subjects were primarily divided into two groups: the IVF-LN (C-IVF with a 50% lower-than-expected oocyte yield) group and the ICSI-LN (ICSI with a 50% lower-than-expected oocyte yield) group.

We observed no significant differences in the day 3 available embryo (87.0 versus 84.8%; p = 0.41), blastocyst formation (61.2 versus 57.9%; p = 0.69), day 5 blastocyst (56.9 versus 54.5%; p = 0.83) or good quality blastocyst (45.4 versus 50.0%; p = 0.83) rates between the IVF-LN and ICSI-LN groups. However, the day 3 good quality embryo rate was significantly higher in the IVF-LN group than in the ICSI-LN group (59.76% vs. 47.46%; p < 0.01). There were no significant differences in the pregnancy (61.8 versus 57.7%; p = 0.50), clinical pregnancy (59.1 versus 53.8%; p = 0.40), ongoing pregnancy (52.2 versus 47.4%; p = 0.45) or live birth (48.6 versus 44.9%; p = 0.55) rates between the IVF-LN and ICSI-LN groups.

For patients with <5 Oocytes and a predicted yield of ≤50%, ICSI did not demonstrate a significant advantage over C-IVF.