P-125 Effectiveness of IMSI technique in enhancing blastocyst formation in male factor infertility
Authors: Anis Hebisha S , Kamal H , Saleh H 
Published: June 2022

Study question

does the use of IMSI technique in sperm selection during ICSI in case of male factor enhance blastocyst formation?

Summary answer

The use of IMSI technique enhanced the ferritization and blastulation rates as well the blastocyst quality in comparison with the conventional ICSI technique

What is known already

Prior to sperm injection the morphology of the sperm cell is evaluated with high magnification Diffraction Interference Contrast (DIC) microscopy. ICSI is performed using morphologically well-shaped spermatozoa selected within the limits of the conventional ICSI inverted microscope magnification of x400. However, it became evident that the morphology of the individual spermatozoon used for microinjection into the oocyte is associated to both fertilization and pregnancy outcome.The impact of nuclear vacuoles in the head of spermatozoa on pregnancy outcome was analyzed too, showing that microinjection of vacuolated sperm reduced the pregnancy rate and was associated with a higher risk for early abortion.

Study design, size, duration

A prospective cohort observational randomized sibling-oocyte study

A total of 300 infertile couples undergoing ICSI were included in the study from August 2020 to July 2021.

Ethical approval from Alexandria University, faculty of Medicine.

Participants/materials, setting, methods

A total of 300 infertile couples undergoing ICSI, Male factor infertility according to the World Health Organization (WHO) criteria 2010, patients with Azoospermia.and sperm concentration less than 0.1 million/mL were excluded.The oocytes of each patient were randomly divided into two groups in 1 to 1 ratio. One group was injected with sperms selected by normal magnification (3357) oocytes and the other group was injected with sperms selected by high magnification (IMSI) technique (3384) oocytes.

Main results and the role of chance

Statistical results according to number of cases showed that IMSI is significantly higher than ICSI in the number of fertilized oocytes (Mean± SD was 9.46±4.10vs. 9.02 ± 4.20, P ≤ 0.001), number of blastocysts (Mean± SD was 4.74±3.42 vs. 4.47±3.27, P = 0.035) and number of good quality blastocysts (Mean± SD was 1.97±2.57 vs. 1.75±2.50, P = 0.009), with No Significant difference in the number of injected oocytes.Comparison between ICSI and IMSI according to rates related to number of oocytes. Statistical results according to rates showed that IMSI is significantly higher than ICSI in fertilization rate (Mean± SD was 84.25 ± 16.57 vs. 80.01 ± 17.95, P ≤ 0.001), and the rate of good quality blastocysts (Mean± SD was 17.04 ± 18.47 vs. 15.59 ± 18.71, P = 0.04). No Significant difference in the blastulation rate P = 0.106. Comparison between ICSI and IMSI according to total number of injected oocytes (n = 6741) Statistical results according to total number of injected oocytes showed that IMSI is significantly higher than ICSI in fertilized oocytes (83.9% vs. 80.6% P = 0.001), and blastocysts with good quality (17.4% vs. 15.7%, P = 0.05). No Significant difference in the total number of blastocysts P = 0.075.

Limitations, reasons for caution

implantation, pregnancy and abortion rates were not included in the study

Wider implications of the findings

Similar to the present result and agreement to our suggestion several studies showed higher fertilization and blastocyst formation with the use of IMSI techniques and others showed higher implantation and pregnancy rates and lower miscarriage rates.Our recommendation is to use IMSI technique during sperm selection for treating infertile couples

Trial registration number

not applicable