Intrauterine Insemination with Special Reference to Density Gradient Centrifugation

Abstract

Since Intra-uterine insemination IUI requires the isolation of motile spermatozoaatozoa, advances in andrology research has helped understand the physiology of male germ cell and allowed development of better and more sophisticated techniques to separate functional spermatozoaatozoa from those that are immotile, have poor morphology or are not capable to fertilize oocytes. When compared with other techniques, Density Gradients Centrifugation (DGC) technique allows maximum yield of motile spermatozoa. Several density media like IxaPrep, Nycodenz, SilSelect, PureSpermatozoa and Isolate have been developed to replace Percoll which, was banned in 1996 due to risk of contamination with endotoxins. Semen analysis, according to the revised, WHO (2010) criteria should be carried out prior to processing the sample. Although sophisticated testing—such as DNA fragmentation analysis, oxidative stress analysis and spermatozoa evaluation for genomic, proteomic and metabolic factor are in research phase, it is more than likely that in future these will help in assessing the suitability of the sample in certain cases of male factor or unexplained infertility. The isolation of functional spermatozoaatozoa from highly viscous ejaculates is a challenge that can be performed enzymatically to liquefy the ejaculate. Special care should be taken when processing HIV, Hep B and Hep C, positive samples. Prior to insemination, the processed sample should be tested to ensure the absence of HIV, Hep B and Hep C. There is no agreement between Andrologists as to what should be the minimum motile count for IUI to be successful. Pregnancies have been reported with counts in range of 1 – 10 million motile spermatozoas. Morphology of the processed sample has limited influence on the final outcome. Finally, single insemination 40 h after the hCG injection should be performed using a soft catheter. Normally, 2nd insemination 24 hrs later is only indicated when the follicle has not ruptured at 40 h post hCG injection.