Artificial oocyte activation with SrCl2 or calcimycin after ICSI improves clinical and embryological outcomes compared with ICSI alone: results of a randomized clinical trial

Abstract STUDY QUESTION Are pregnancy and birth rates affected by artificial oocyte activation (AOA) with SrCl2 or calcimycin after ICSI for couples with male-factor infertility linked to abnormal sperm morphology or for couples with previous ICSI cycles of unexplained low fertilization or inadequate fertilization associated with impaired oocyte morphology? SUMMARY ANSWER AOA with either SrCl2 or calcimycin can improve the rates of clinical pregnancy, ongoing pregnancy and live birth compared with ICSI alone, and the two agents have diverse effects for different subgroups of patients. WHAT IS KNOWN ALREADY ICSI is a successful treatment for infertility, but not in all individuals. AOA has potential to overcome inadequate fertilization in ICSI. Calcimycin and SrCl2 are candidate agents for AOA, but their effectiveness remains to be compared. STUDY DESIGN, SIZE, DURATION This study was a randomized, open-label, three-arm, parallel-group, double-centre, superiority trial conducted between April 2015 and January 2016. The study evaluated the effects of AOA with calcimycin or SrCl2 for clinical pregnancy rates after ICSI and included 343 couples divided into three groups. PARTICIPANTS/MATERIALS, SETTING, METHODS Couples were included if they had two previous ICSI cycles of no or low fertilization (0-30%) with unknown causes or impaired oocyte morphology. Male-factor infertility cycles (frozen-thawed sperm, surgically retrieved sperm or ejaculates contained