Department of Obstetrics and Gynaecology

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Browsing Department of Obstetrics and Gynaecology by browse.metadata.advisor "Franken, D. R."

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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 effect of solubilized homologous zona pellucida on the human acrosome reaction, sperm-zona binding and motion characteristics of capacitated human spermatozoa
    (Stellenbosch : Stellenbosch University, 2003-12) Bastiaan, Hadley Saville; Franken, D. R.; Menkveld, Roelof; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Obstetrics and Gynaecology.
    ENGLISH ABSTRACT: CHAPTER 1 provides literature based background information to emphasize the use of a sequential, multistep diagnostic schedule for couples in an assisted reproductive program as well as the clinical importance of sperm morphology as recorded by strict criteria during the diagnostic approach of the infertile couple. Furthermore, the chapter includes evidence underlining the growing need for the implementation of the physiologically induced acrosome reaction as an important contribution to the assisted reproductive program. The zona pellucida-induced acrosome reaction (ZIAR), sperm-zona interaction as well as computer-assisted semen analyses were investigated. CHAPTER 2 provides detailed experimental protocols of the materials and methods used in the study. CHAPTERS 3-6 each represent a separate study that was prepared as a scientific paper and encompass the experimental research undertaken in the reproductive biology research laboratory at Tygerberg Hospital to address important aspects of human acrosome processes. In the first study, we aimed to evaluate the regulatory role of the Gi-like protein during the AR of normal sperm donors and the role of intact acrosomes during sperm-zona binding. It seems that pertussis toxin-sensitive Gi-like protein in human spermatozoa plays an important regulatory role in the ZIAR and this underlines the importance of intact acrosomes during sperm-zona binding. In the second study, we aimed to evaluate the relationship between the ZIAR and the percentage normal spermatozoa as well as the sperm-ZP binding potential among men referred for a routine semen analysis. ZIAR testing should become part of the second level of male fertility investigations, i.e., sperm functional testing, since 15% of the andrology referrals revealed an impaired AR response to solubilized ZP. In the third study, we aimed to evaluate the possible relationships between the sperm morphology, the acrosome responsiveness to solubulized human ZP and the sperm-zona binding potential among consecutive andrology referrals and randomly selected IVF cases. ZIAR results provide further information regarding dysfunctional sperm and can be used as an additional diagnostic test since the results predicted fertilization failure during IVF treatment. In the fourth study, we aimed to evaluate changes in the sperm motion characteristics and the occurrence of hyperactivated motility after exposure to ZP among andrology referrals. Solubilized human ZP induces hyperactivated motility among sperm populations that have been capacitated under laboratory conditions. Capacitated spermatozoa have an elevated percentage hyperactivated cells that correlate with the percentage normal spermatozoa in the ejaculate. CHAPTER 7, the general discussion, is brief and concise to avoid unnecessary repetition, underlines the validity of a sequential, multistep diagnostic approach and concludes with the recommendation that the ZIAR should form part of the diagnostic tools in the assisted reproductive program.
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    Evaluation of gamete dysfunction as a cause of failed human in vitro fertilization
    (Stellenbosch : Stellenbosch University, 2000-12) Esterhuizen, Aletta Dorothea; Franken, D. R.; Stellenbosch University. Faculty of Medicine & Health Sciences. Dept. of Medicine.
    ENGLISH ABSTRACT: Chapter 1 provides literature based background information on the clinical importance of sperm morphology as recorded by strict criteria during the diagnostic approach of the infertile couple. Furthermore, the use of a sequential diagnostic schedule for couples in an assisted reproductive programme is emphasized. The author revisited the literature on chromatin packaging of spermatozoa and addresses this issue as an additional semen parameter providing information relating to DNA damaged spermatozoa. The chapter also includes evidence underlining the growing need for the implementation of the acrosome reaction as an important contribution to the assisted reproductive programme. Chapter 2 provides detailed descriptions of the material and methods used during the study. Chapter 3 is sub-divided into 5 sections, each of which represents a separate study that was prepared as a scientific paper. The study included 338 couples consulting for infertility treatment at various gynaecologists in Pretoria and Johannesburg. The diagnostic assisted reproductive laboratory support was provided by the Andrology laboratory of Drs du Buisson and partners from Pretoria. In the first study the role of chromatin packaging as an indicator of in vitro fertilization rates, the semen samples from 72 men were used to record their chromatin packaging quality as well as their sperm morphology classification. Significant different percentages CMA3staining (mean±SE) were recorded among the 2 morphology groups, namely 65.9%±3.5 and 44.5%±1.7 (p=0.001). Using cut off values for chromatin packaging established during the first study, the second study utilized semen from 140 men in the in vitro fertilization (IVF) and intracytoplasmic sperm injection programme (ICSI) to analyze for sperm concentration, motility, morphology and chromatin packaging (CMA3).IVF and ICSI data were stratified using 3 basic cut off values for CMA3staining, namely <44%, >44-60% and >60%. The study concluded that results on the chromatin packaging quality of spermatozoa could be used as an additional parameter of sperm quality since it could provide valuable information on decondensation status of a given sperm population. The third study aimed to establish zona pellucida induced acrosome reaction response (ZIAR) among 35 couples with normal and G-pattern sperm morphology and repeated poor fertilization results during assisted reproduction treatment. Interactive dot diagrams, divided patients into 2 groups i.e. ZIAR<15% and ZIAR>15% with mean fertilization rates of 49% and 79%, respectively. The study concluded that the ZIAR test has diagnostic potential, since it can assist the clinician to identify couples that will benefit from ICSI therapy. The forth study revisited the importance of micro-assay for acrosome reaction determinations in a diagnostic andrology laboratory. The micro-assay not only allows the use of a single zona pellucida, but also facilitates the future possibility of using recombinant zona pellucida proteins in a diagnostic test system. The final study in Chapter 3 includes results obtained from 49 couples (172 oocytes) and aimed to evaluate the role of chromatin packaging and sperm morphology during sperm-zona binding, sperm decondensation and the presence of polar bodies among 170 oocytes that failed in vitro fertilization (IVF). Odds ratio analyses indicated that being in the a group with elevated CMA3 staining i.e. >60%, the risk of decondensation failure increases 15.6 fold relative to normal CMA3 staining <44%. Chapter 4 underlines the validity of the sequential diagnostic approach and summarizes the results and value of a multistep diagnostic scheme. The chapter concludes with the recommendation that both chromatin packaging quality and zona pellucida mediation of the acrosome reaction should be part of the diagnostic tools in the assisted reproductive programme.
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    The interaction between human spermatozoa and its homologous zona pellucida : scientific advances and clinical significance
    (Stellenbosch : Stellenbosch University, 2002-12) Oehninger, Sergio C.; Franken, D. R.; Stellenbosch University. Faculty of Medicine & Health Sciences . Dept. of Obstetrics & Gynaecology.
    ENGLISH ABSTRACT: Infertility is a very common problem worldwide. Recent data have shown that disorders of the male represent the most common single defined cause of infertility. This proposal examines the clinical significance and fundamental physiological aspects of human gamete interaction. These studies are focused on the assessment of the cellular-molecular mechanisms involved in human sperm binding to its homologous zona pellucida resulting in the physiologic induction of the acrosome reaction. We have developed and validated in vitro bioassays that assess specific steps of the fertilization process that are critical for early embryo development. The results of our translational research have already had a significant impact on the overall evaluation of male infertility and on the clinical management of the infertile man in the assisted reproduction arena. Furthermore, the unveiling of the basic mechanisms involved in human gamete interaction will ultimately allow for both (i) the development of new male reproductive diagnostic capabilities and (ii) the design of improved and safer therapies aiding conception in childless couples suffering from male infertility.