Oocyte Degeneration After ICSI Is Not an Indicator of Live Birth in Young Women

Abstract

IntroductionIntracytoplasmic sperm injection (ICSI) was introduced in 1990s as one of the most dramatic breakthroughs in assisted reproductive technology. Even with advances in ICSI technology, this mechanical micromanipulation carries a 5 to 19% risk of oocyte degeneration. Whether the presence of oocyte degeneration reflects the sibling oocyte quality and predicts the sibling embryo development potential and clinical pregnancy outcomes remains controversial. There is no study showing the competence of the sibling embryos from the prospective of cumulative live birth rate. Whether oocyte degeneration is associated with poor quality of the remainder of the cohort remains further to be elucidated.MethodThis retrospective observational study included a total of 488 OPU cycles underwent ICSI with fresh cleavage stage embryo transfer and successive frozen/thawed embryo transfer (FET) cycles from January 2018 to December 2019. All female patients were under the age of 35 years, and underwent ICSI with or without oocyte degeneration (OD). Cycles with at least one oocyte degenerated were defined as oocyte degeneration group (OD group), and cycles with no oocyte degenerated were defined as non-OD group. The OD group was further divided to three subgroups according to different oocyte degeneration rate (<10%, 10-20%, and >20%).ResultsThere were no significant differences with regards to implantation rate (38.5% vs 35.1%, P=0.302), clinical pregnancy rate (54.9% vs 50.3%, P=0.340), and LBR per OPU cycle (47.0% vs 42.9%, P=0.395) between OD and non-OD groups. Initial gonadotropin dosage, E2 level on hCG day and the number of matured oocytes appeared to be independent risk factors for OD. The adjusted odds ratio of live birth rate per OPU cycle were similar in different oocyte degeneration rate subgroups. The ongoing pregnancy/LBR per transfer in FET cycles was not significantly different between OD group and non-OD groups (38.8% vs 43.9%, P=0.439). The cumulative LBR per OPU cycle was also comparable between OD and non-OD group (63.4% vs 64.8%, P=0.760).ConclusionThe results provide cycle-based evidence that the presence of oocyte degeneration after ICSI is not an indicator for predicting the cumulative live birth rate per OPU cycle in young women.