IMSI is beneficial in cases of advanced maternal age: a prospective randomized study

Abstract

This study evaluated advanced maternal age as a rationale for performing intracytoplasmic morphologically selected sperm injection (IMSI). Couples undergoing intracytoplasmic sperm injection (ICSI) as a result of advanced maternal age (⩾37 years old) were randomly allocated to receive one of two sperm selection procedures (ICSI, n=33; IMSI, n=33). The groups were compared with regard to cycle outcomes. Fertilization rate and high-quality embryo rate on day 3 of development were similar between ICSI and IMSI groups. However, blastocyst formation rate (19.6% versus 34.1%, P=0.001) and number of transferred embryos (1.1±0.3 versus 1.5±0.6, P=0.003) were higher in the IMSI group. IMSI cycles showed significantly higher implantation rate (12.1% versus 38.3%, P=0.026) and pregnancy rate (13.8% versus 60.0%, P<0.001). IMSI positively influenced the blastocyst formation rate (regression coefficient, RC, 15.00, R2 49.9%, P=0.001) and implantation rate (RC 24.04, R2 9.6, P=0.027), and was a determinant for increased odds of pregnancy (OR 9.0, 95% CI 2.17–37.38, P=0.001). In couples with advanced maternal age, IMSI performance results in higher blastocyst formation, implantation and clinical pregnancy rates as compared with conventional ICSI.The objective of this study was to evaluate the advanced maternal age as a rationale for performing intracytoplasmic morphologically selected sperm injection (IMSI). This study included couples undergoing intracytoplasmic sperm injection (ICSI) as a result of advanced maternal age (⩾37 years old). Couples were randomly allocated to receive one of two sperm selection procedures (ICSI or IMSI). Fertilization rate and high-quality embryos rate on day 3 of development were similar between ICSI and IMSI groups. However, blastocyst formation rate and number of transferred embryos were higher in the IMSI group. IMSI cycles showed significantly higher implantation and pregnancy rates. The IMSI procedure positively influenced the blastocyst formation and implantation rates and was a determinant to the increased odds of pregnancy. This study demonstrates that, in couples with advanced maternal age, IMSI performance results in higher blastocyst formation, implantation and pregnancy rates as compared with conventional ICSI.