Does timing in ICSI cycle affect oocyte quality and reproductive outcomes? A prospective study.

Abstract

To evaluate the association of time intervals between various steps of the intracytoplasmic sperm injection (ICSI) cycle with oocyte quality and reproductive outcomes. We conducted a prospective study among patients undergoing ICSI cycles in an academic hospital between May 2017 and January 2019. The time intervals between the various steps of cycles were recorded. The ICSI cycles were categorized according to the different time intervals; human chorionic gonadotropin (hCG) injection to oocyte pick up (hCG-OPU) (≤ 36h and > 36h), OPU-denudation (≤ 2h and > 2h), and denudation-ICSI (≤ 2h and > 2h). The main outcome measures were oocyte dysmorphisms, fertilization, cleavage, biochemical, and clinical pregnancy rates. A total of 613 ICSI cycles using fresh autologous oocytes were included in this study. After adjusting for confounders, the hCG-OPU interval was associated with the presence of cytoplasmic granulation, inclusion body, and also the total number of morphologically abnormal premature oocytes in the cycle (P = 0.02, P = 0.04, P = 0.008, respectively). OPU-denudation interval was associated with cytoplasmic granulation and extended perivitelline space of the oocytes (P = 0.006 and P = 0.03, respectively). The denudation-ICSI interval was only associated with cytoplasmic granulation (P = 0.01). However, hCG-OPU, OPU-denudation, and denudation-ICSI intervals were not significantly associated with fertilization, cleavage, biochemical, and clinical pregnancy rates. All the studied time intervals between various steps of ICSI procedure could affect oocyte quality, but the oocyte dysmorphisms were mainly associated with hCG-OPU interval. However, the time intervals were not associated with fertilization, cleavage, and pregnancy outcomes.