Abstract
Study question
Is there any difference in this technique(swim-in) according to clinical results in ICSI cycles?
Summary answer
Fertilization rates are significantly better with this new technique(swim-in). There is no difference in pregnancy and ongoing pregnancy rates between swim-in and DGS techniques.
What is known already
Sperm separation is crucial in assisted reproductive technologies, based on different principles like migration, filtration, or density gradient centrifugation techniques. However, there are some studies that centrifugation steps and using gradient solutions may increase sperm DNA fragmentation. On the other hand, multiple contacts to different plastic surfaces such as pipettes, plastic tubes, etc., and also pipetting the ejaculate in sperm preparation may have detrimental effects. The ideal sperm separation technique should be non-invasive, not time-consuming, easy, and cost-effective, not cause sperm damage or non-physiological alterations of the separated sperm cells, eliminate dead spermatozoa and other cells, including leukocytes.
Study design, size, duration
This is a prospective randomized study between 01/02/2019...01/01/2021. Sperms were prepared either with this new technique that we call “swim-in”(n = 359) or with density gradient centrifugation(n = 404) before microinjection (ICSI). Fertilization rates, clinical pregnancy rates, and on-going pregnancy rates were compared between groups. Sperm motility is less than%20 patients are not included in the study. t-test and Chi-square test used. p < 0.05 significant.
Participants/materials, setting, methods
For this new centrifugation free technique(swim-in), a Braun injector, 21G green needle, and sperm washing medium are used. First, we pulled a 0.5 ml sperm wash medium in a Braun injector. After sperm liquefaction, we put Braun injector with the needle in the sperm cap perpendicularly and waited 30 minutes at 37-degree Celcius. Sperms swam through the needle to the injector used for ICSI. For DGC sperms were prepared according to the 2015 WHO manual. Main results and the role of chance: We try to make a centrifugation-free, gentle, cost-effective, and easy sperm preparation technique and called it a swim-in technique. Groups were comparable according to mean age, collected oocyte numbers, and oocyte maturation ratios. Fertilization rates are%73,2(1786/2438) vs%66,9(2167/3237) respectively for swim-in and DGC groups. Clinical pregnancy rates are%45,1 vs%42,3 respectively for swim-in and DGC groups. On-going pregnancy rates are%41,5 vs%39,6 for swim-in and DGC respectively. There is a significant difference between the two techniques according to fertilization rates but no difference according to clinical pregnancy and ongoing pregnancy rates.
Limitations, reasons for caution
Sperms can move by their own motility from ejaculate to the sperm washing medium for that reason with severe sperm problem patients are not suitable for this technique.
Wider implications of the findings: This technique is centrifugation free so there are no detrimental g-forces. The needle used may mimic the physiological environment like Uterine Tube. Alternative sperm washing mediums like follicular fluid or chemical attractor progesterone rich medium can be used.DNA fragmentation rates and live birth rates should be established for future aspect.
Trial registration number
Not applicable
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