Browsing by Author "Rijsdijk, Michelle"

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    A comparison of three spermatozoa selection techniques for Intracytoplasmic Sperm Injection (ICSI) using swim-up, Cumulus Oophorus Model and PICSI ® Dish
    (Stellenbosch : Stellenbosch University, 2015-12) Rijsdijk, Michelle; Franken, D. R.; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Obstetrics and Gynaecology.
    ENGLISH ABSTRACT: Introduction: Spermatozoa selection for Intracytoplasmic Sperm Injection (ICSI) is a paramount factor in the outcome of a fertility treatment cycle. Nature has perfected the selection process by using the cumulus matrix to select spermatozoa that are morphologically and genetically normal. Aim: To determine which method of semen preparation delivers the best results in terms of spermatozoa selection for ICSI. Methods: Patients were randomized into 3 groups of spermatozoa selection techniques namely the routine swim-up or density gradient, the Cumulus Model or the PICSI® dish (hyaluronic acid). The prepared collected spermatozoa were used to make slides to record the percentage of normal spermatozoa (morphological staining), the capacitational status (chlorotetracycline test), chromatin packaging quality (chromomycin A3 (CMA3) staining) and the DNA quality (acridine orange staining). These results were then compared to the fertilization, cleavage, pregnancy and implantation rates of the patients used in the study. Results: All three groups displayed improvements in morphology, capacitational ability, chromatin packaging quality and DNA quality (or fragmentation). There was no significant difference in pregnancy rates between the groups and no difference in implantation rates. The PICSI® group did however show a significant improvement in the chromatin packaging quality, only if the baseline values were low. Conclusions: All 3 groups of spermatozoa selection techniques showed improvements in spermatozoa quality. The swim-up/gradient group showed a statistical improvement in the fertilization rate when compared to the cumulus and PICSI® groups. PICSI® showed a greater improvement in selected spermatozoa parameters when baseline values for CMA3 were low.
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    The role of the cumulus oophorus complex during spermatozoa capacitational events
    (Stellenbosch : University of Stellenbosch, 2005-12) Rijsdijk, Michelle; Franken, Daniel R.; University of Stellenbosch. Faculty of Health Sciences. Dept. of Obstetrics and Gynaecology.
    Chapter 1 contains a review dealing with nuclear and morphological changes during spermatogenesis and spermatozoa transport with emphasis on the maturation of spermatozoa, capacitation, acrosome reaction and the interaction with the cumulus oophorus complex (COC). The oocyte and cumulus oophorus complex is also discussed particularly on the topic of maturity (oocyte and cumulus maturity). Also presented is a review of the fluorescent binding agents, namely Fluorescein Isothiocyanate labeled with Pisum sativum (FITC-PSA), Chlorotetracycline test (CTC) and Chromomycin A3 (CMA3). Chapter II describes all the materials and methods used during this study. Routine semen analysis is described with emphasis on normal spermatozoon morphology according to strict criteria. The evaluation of capacitation and acrosome reaction (AR) using the CTC and PSA-FITC staining methods as well as the evaluation of spermatozoon nuclear chromatin packaging using the CMA3 staining method is described. Chapter III represents the results recorded in this study. Compared with those spermatozoa cultured in medium alone, spermatozoa exposed to the cumulus mass were more likely to be capacitated and acrosome reacted, with a distinct increase in chromatin packaging quality. A general discussion of the results and future applications are discussed in Chapter IV. In short An in vitro model for spermatozoa penetration through the cumulus oophorus was established. The model can be applied to investigate the effect of the cumulus oophorus on sperm functions and to assist in the selection of functional sperm for intracytoplasmic sperm injection therapy. All relevant references are presented in Chapter V .