Magister Legum - LLM / In this research, I carefully and coherently examine Chapter 19 of the Children's Act 38 of 2005 as the first legislation to afford surrogate motherhood agreements legal recognition in South Africa. I argue that the application of Chapter 19 imposes a number of unwarranted limitations on several of the constitutional rights of the parties to a surrogacy agreement. In addition, I propose that Chapter 19 is not in accordance with the principal of the best interests of the child. I examine the history of surrogate motherhood in South Africa and establish that, prior to the enactment of Chapter 19, no legislation expressly afforded surrogate motherhood agreements legal recognition. Hence, prior to the enactment of Chapter 19, parties who entered surrogacy agreements could, first, not rely on the agreement to enforce contractual obligations, and secondly, the legal positions of the parties to the agreement were uncertain. Thirdly, a child born of a surrogacy agreement was seen as the child of the surrogate mother and not of the commissioning parents. / South Africa

The Asian elephant (Elephas maximus), a charismatic ‘flagship species’, is threatened by extinction in the wild, and the development of self-sustainable captive populations is a key conservation challenge. A third of the Asian elephant population is presently in captivity and information on the reproductive status, especially in females, is still lacking to a large extent. The onset of estrus in female Asian elephants is not associated with any visible physical signs, thus making the assessment of the reproductive status rather difficult. One approach to understanding reproductive cyclicity of animals is through generating profiles of reproductive hormones in blood (Wiseman et al. 1983; Brown et al. 1999, 2004). Profiles of reproductive hormones such as progesterone (P4), estrogen, luteinizing hormone and follicle stimulating hormone have already being demonstrated in Asian elephants (Brown et al. 1999, 2004; Brown 2000). In these studies, the reproductive status of females, maintained in zoos/captivity, was characterized based on circulating levels of hormones in blood samples. This is difficult to implement in the case of semi-captive or wild populations of elephants due to practical, legal and ethical considerations. In order to overcome this problem and to better understand the estrous status of female elephants, it is important to develop and validate non-invasive methods to monitor the reproductive status of female Asian elephants. An alternative approach to evaluating the reproductive status of females is to consider behavioral responses shown by males towards chemical signals produced by females to advertise their reproductive status. In order to understand the reproductive status of the individual belonging to the opposite sex, studies have shown that elephants rely on a variety of chemical signals produced in biological fluids such as urine, temporal gland secretion, inter-digital gland secretion, etc. (Krishnan 1972; Rasmussen & Schulte 1998). Chemical signaling is one of the prominent modes of communication in elephants, especially with respect to locating potential mates (Sukumar 2003). Thus, in most cases, elephants usually employ specific behavioral responses, for example sniff, check and place behaviors of trunk, for investigating the reproductive status of the conspecific individual, belonging either to the same or the opposite sex (Rasmussen et al. 1996; Schulte & Rasmussen 1999; Bagley et al. 2006). The objectives of the thesis are two-fold. First, to develop a non-invasive method of reproductive monitoring from fecal hormonal metabolites and also to understand the possible role of feces as an inter-sexual signal. The main body of thesis is divided into four chapters. 1) Development and validation of a non-invasive method to estimate progesterone metabolite in feces, to monitor the reproductive cyclicity of female elephants (Chapter 2). 2)Generation and characterization of progesterone and its metabolite, 5α-P-3-OH, profiles of semi-captive females using the developed non-invasive method to measure fecal metabolites (Chapter 3). 3) Validation of developed methodology and assay systems to a wild-population of female elephants (Chapter 4). 4) Feces as a potential source for inter-sexual chemical signaling in Asian elephants (Chapter 5). The above studies were carried out on semi-captive male and female elephants maintained in the forest camps of Mudumalai Wildlife Sanctuary (MWLS), Tamil Nadu and Bandipur National Park (BNP), Karnataka, India (Chapters 2, 3 and 5). For Chapter-4, free-ranging females of the MWLS were examined. 1. Development and validation of a non-invasive method to estimate progesterone metabolite in feces, to monitor the reproductive cyclicity of female elephants Niemuller et al. (1993) generated a profile of the progesterone metabolite, 5βpregnanetriol, to assess the estrous phase of Asian elephants based on non-invasive urine sampling. However, the collection of urine is difficult and to some extent impossible in the case of semi-captive and as well as that of wild elephants. Thus, the method of choice in this study was the development and validation of a non-invasive approach to measure fecal progesterone metabolites to assess reproductive status of females. Sampling was carried out at monthly intervals on three female elephants at the MWLS forest camp, while three other females maintained at the BNP forest camp were sampled fortnightly. An enzyme linked immuno-sorbent assay was developed to measure the concentration of the progesterone metabolite, 5α-P-3OH in the fecal samples of the semi-captive females. Using varying concentrations of the hapten (5α-P3OH), from low (0.1 mM) to high (1 mM), a standard curve was first generated, which had a linear range between 0.25 mM to 62.5 mM, with an EC50 of 1.37 mM. The linear range was then used to detect the concentrations of 5α-P-3OH in the fecal samples of females examined. The non-invasive method was further validated as there existed a positive correlation (p<0.1) between the levels of fecal 5α-P-3OH and that of concentration of circulating P4, measured in blood samples. This is the first valid documentation of a non-invasive method based on fecal progesterone metabolite pattern in order to assess the reproductive status of the female Asian elephants. 2. Generation and characterization of reproductive hormone profiles of semi-captive females using the developed non-invasive method to measure fecal metabolites With the establishment of a non-invasive method to understand occurrence of estrus in female elephants (described in Chapter 2), attempts were made to generate hormonal profiles over a longer time interval through more frequent sampling. Based on sampling at weekly intervals, the concentrations of both fecal 5α-P-3OH and that of native P4 hormone in the blood were determined, and the females were then identified as belonging to different reproductive states of hormonal cycling (follicular and luteal phases), non-cycling and pregnant categories. Of the 7 females sampled at both MWLS and BNP, three distinct categories of hormone-metabolite profiles emerged. The first category included four females that showed regular cyclicity throughout the sampling period, as monitored through the measurement of fecal 5α-P-3OH and serum P4 levels. The estrous cycle of all the four females was divided into two phases (follicular and luteal), based on the patterns of fecal 5α-P-3OH and serum P4 concentrations. The follicular phase of the estrous cycle was assigned when the values of both fecal 5α-P-3OH and serum P4 remained below 0.3 µg/gm and 0.3 ng/ml, respectively, for a considerable time period (viz. >2 wk). However, the luteal phase was characterized, when the levels of fecal 5α-P-3OH and serum P4 remained at or above 0.3 µg/gm and 0.3 ng/ml respectively, over a period of more than 2 - 3 wk. The second category had two females showing a ‘flat-lining pattern’ for the levels of fecal 5α-P-3OH and serum P4 concentrations, without any peak or dip in their concentrations. Since the reproductive pattern for both these females was flat-lined throughout their sampling period (51 wk), maintaining the levels of fecal 5α-P-3OH and serum P4 below 0.3 µg/gm and 0.3 ng/ml respectively, the females were considered to be non-cycling or anestrus. The third category had one female in which the levels of both fecal 5α-P-3OH and serum P4 measured were consistently high throughout the entire sampling period (26 wk). The levels of both fecal -P-3OH and serum P4 were above 0.3 µg/gm and 0.3 ng/ml, respectively. At the end of the sampling period, this female delivered a male calf; thus, the measured concentrations of fecal 5α-P-3OH and serum P4 signified the levels maintained during the gestational phase of this female. Sampling and hormonal analyses were also carried out for a male in the MWLS forest camps to investigate the baseline concentrations of fecal 5α-P-3OH and serum P4. The male showed consistently low concentrations of both fecal 5α-P-3OH and serum P4 throughout the sampling period (16 wk), below the margin of 0.3 µg/gm and 0.3 ng/ml, respectively. In this part of the study, it was confirmed that the reproductive status of a female elephant can be correctly assessed on the basis of measurements of fecal 5α-P-3OH alone, with repeated sampling of the female over a longer time scale. It was also shown that the strength of the positive correlation between the concentrations of the fecal 5α-P3OH and the serum P4 increased (p<0.01) for a larger sample size than that obtained for a comparatively smaller sample (described in Chapter 2). 3. Validation of developed methodology and assay systems to wild-population of female elephants So far, the non-invasive method to estimate fecal progesterone metabolite in order to predict occurrence of estrus of elephants was largely applied to semi-captive females (described in Chapters 2, 3). However, the necessity of such a method is being recognized for assessing the reproductive status of free-ranging females. Several findings have described differences in the rate and type of steroid metabolite excretion among individuals maintained under different diet regimes (Wasser et al. 1993; Smith et al. 2006). For instance, female elephants in the forest camps are provided with supplementary diet consisting of sugarcane, rice and millets. This diet is strikingly different from the feeding materials consumed by wild/free-ranging elephants (Sukumar 2003). Therefore, differences in dietary components can potentially influence the fecal steroid metabolites’ excretory patterns shown by semi-captive vis-a-vis wild females, which can affect the validity of measuring fecal 5α-P-3OH to predict females’ reproductive status. In order to examine this problem, the non-invasive method was applied to the population of wild elephants in the forests of MWLS, through random one time sampling of 30 individual female elephants. The steroid extraction efficiency (73 ± 11.0%, mean ± S.D., n =30) determined for the fecal samples collected from the wild females was not significantly different from the coefficient calculated in the case of the semi-captive females (80 ± 4.3%, mean ± S.D., n = 38). This indicated that dietary differences between wild and captive elephants did not influence levels of fecal hormonal metabolites in feces, unlike earlier observations on baboons (Wasser et al. 1993), old world primates (Wasser et al. 1988) and sheep (Smith et al. 2006). The values of the fecal allopregnanolone determined in the case of the wild females, ranged from as low as 0.06 µg/gm to as high as 23µg/gm of the sample, thus showing the heterogeneity of the samples, indicating that the females may be belonging to different reproductive phases. However, since sampling was carried out randomly, with an adult female being sampled just once, at this stage, it is not possible to identify or elaborate on the reproductive phase of the females. This is the first study reporting the values of the fecal progesterone metabolite in female Asian elephants in the wild. Further studies may be required to carry out long term monitoring of the wild females, through repeated collection of fecal samples over time from particular female. 4. Feces as a potential source for inter-sexual chemical signaling in Asian elephants In this Chapter-5, behavioral trials were conducted on male elephants to understand the role of fecal matter in conveying inter-sexual chemical signals. This was demonstrated by analyses of specific chemosensory behavioral responses shown by males towards the fecal samples of females that were strangers and belonging to different reproductive stages. Males showed four prominent behavioral responses namely ‘distant sniff’, ‘close sniff’, ‘check’ and ‘place’ towards the fecal samples of females. The sum of frequencies of these four responses (distant sniff, close sniff, check and place) was much higher for samples of the follicular (pre-ovulatory) phase females as compared to those of the luteal (post-ovulatory) phase females (p<0.005). Thus, for the first time, it was shown that male elephants are able to discriminate the different reproductive phases of females based on their specific behavioral response towards the fecal samples of the opposite sex. In conclusion, the thesis has focused on understanding and providing new insights regarding the reproductive biology of the female Asian elephants. This has been achieved through the development of the non-invasive method based on measuring the concentrations of the fecal progesterone metabolite and through the analyses of the chemosensory responses performed by the males towards the fecal samples of strange females. These methods can potentially be applied to the populations of both wild and captive/semi-captive female elephants in order to evaluate their reproductive status, through non-invasive measures. The information derived from the application of such methods will help in understanding the reproductive potential of the wild elephants under various environmental and ecological conditions. Further, the non-invasive measurement of reproductive hormones will help in monitoring the reproductive state of the individuals and thus aid in planning strategies for the welfare and management of the elephants maintained in captive or semi-captive conditions.

Cryopreservation of fish ovarian tissue fragments can be a viable alternative to cryopreservation of oocytes and embryos. The ability to cryopreserve both maternal and paternal gametes would provide a reliable source of fish genetic material for scientific and aquaculture purposes. The main aim of the present study was to develop an in-vitro culture protocol and cryopreservation protocol for zebrafish ovarian tissue fragments. In-vitro culture protocol for the tissue fragments containing stage I and stage II follicles were developed and the growth assessment of follicles were evaluated using biomarkers. To develop the cryopreservation protocol using control slow cooling method, the effect on freezing medium, cryoprotectants and cooling rate on the tissue fragments were investigated. The in-vitro culture experiments showed that L-15 medium (pH 9) containing 100mIU/ml FSH along with 20% FBS was effective for tissue fragments containing stage I and II follicles to grow in-vitro. The growth of the ovarian follicle stages was confirmed by the level of expression of p450aromA and vtg1 gene. The optimal cryopreservation protocol for the ovarian tissue fragments was found as 2M methanol+ 20%FBS in 90% L-15 medium with the cooling rate of 4°C/min. Although the highest survival rate obtained for stage II follicles within the fragments was 68.2±1.9% and stage I follicles within the fragments was 55.4±2.3% using TB staining, it showed a significant decrease in their ATP levels. This is the first study carried out on the zebrafish ovarian tissue fragments. Study on cryopreservation of the ovarian tissue fragments and development of the in-vitro culture protocol and use of biomarkers for the ovarian tissue fragments were reported here for the first time. The outcomes of this study have provided useful information for future cryopreservation protocol development.

The chromosome constitution of human cleavage stage embryos has been extensively investi-gated using a variety of techniques, revealing high levels of aneuploidy and mosaicism. However, the final phase of preimplantation development, the blastocyst stage has received relatively little attention mostly because it is only recently that embryo culture has become sufficiently well optimised to reliabley generate blastocysts. One of the aims of this study was to examine blastocyst cytogenetics, characterising the extent and variety of aneuploidy and, where possible, determining the origin of the abnormalities detected. Both the frequency of aneuploidy and the incidence of mosaicism were significantly lower in the 52 embryos generated by 20 patients that had successfully undergone the first cellular differentiation, producing trophectoderm (TE) and inner cell mass (ICM). Valuable tools for the detailed chromosomal analysis of blastocysts, used in both research and clinical contexts, were comparative genomic hybridization (CGH) and array CGH (aCGH). However, validation of these methods, especially aCGH, was required in order to verify accuracy. A low error rate and a low misdiagnosis risk were demonstrated. The morphology of 1397 embryos at the cleavage and blastocyst stages from 229 patients was evaluated in relation to their chromosomal complement. The results obtained during this part of the project showed that, in general, there is little correlation between cleavage stage morphology and chromosome status. A weak link between morphology and aneuploidy, however, was found for embryos at the blastocyst stage. Chromosomally normal female embryos had a tendency to grow faster than male embryos at the cleavage stage and therefore tended to achieve superior morphological scores, whereas the trend was reversed at the blastocyst stage. Abnormal embryos carrying types of aneuploidy compatible with formation of a clinically recognised pregnancy had morphologies indistinguishable from those of euploid embryos. This study also aimed to utilise aCGH for the preimplantation genetic diagnosis (PGD) of imbal-ances due to structural chromosome rearrangements (e.g. translocations) in 39 carriers, a total of 139 embryos were assessed. The data obtained revealed that carriers of Robertsonian translocations are at increased risk of aneuploidy affecting additional chromosomes not involved the translocation, a phenomenon known as an interchromosomal effect (ICE). Finally, the clinical outcomes of 300 patients undergoing preimplantation genetic screening (PGS) using aCGH, for various different indications, were evaluated at both the cleavage (795 embryos) and blastocyst stages (1097 embryos). The pregnancy rate following cleavage stage biopsy was significantly lower than following blastocyst stage biopsy. The miscarriage rate was significantly reduced following PGS for patients with recurrent miscarriages. This work provided promising data supporting the clinical use of comprehensive chromosome analysis for the screening or diagnosis of preimplantation embryos and also yielded scientifically useful information concerning the frequency and nature of aneuploidy at the final stage of development before implantation.

Explaining the origin and maintenance of biodiversity is a central goal in ecology and evolutionary biology. Some of the most important, theoretical explanations for this diversity centre on the evolution of life histories. Comparative studies on life history evolution, have received significant attention in the zoological literature, but have lagged in plants. Recent developments, however, have emphasised the value of comparative analysis of data for many species to test existing theories of life history evolution, as well as to provide the basis for developing additional or alternative theories. The primary goal of this study was to explore existing theories of life history evolution using a dataset of demographic information in the form of matrix population models for a large number of plant species. By projecting average matrix population models for 207 plant species, life tables and fecundity schedules were obtained and, in turn, were used to estimate relevant life history parameters. These parameters were then used to explore the i) lability of life history traits in plants ii) their continuum of life history variation, iii) the evolution of senescence and iv) the significance of demographic entropy in population ecology. Elasticities and sensitivities of life history traits showed significant phylogenetic signal compared to other life history traits, although, all the values of phylogenetic signal observed were &lt; 1 indicating that life history traits are generally labile. Eighty one percent of species in the datset had mortality curves that increased with age compared to one hundred percent of species that showed a reproductive value curve that decreases with age at the end of life. In particular, the parameters that measured pace and duration were inversely related suggesting in general, the presence of senescence in our data set. Finally, the tenets of the directionality theory based on demographic entropy were generally not confirmed. This study provides an important contribution to the life history evolution of iteroparous perennial plants and confirms existing theories on life history evolution.

Increasing shares of European women are making large investments in their human capital. Whether and to what extent these investments are in conflict with reproductive behaviour are issues that have repercussions for fertility levels. Using two Eurobarometer survey data (2006 and 2011) on individuals clustered in the 27 EU countries, I investigate the relationship between women's education and lifetime fertility intentions. Results suggest that a positive association between women's level of education and lifetime fertility intentions exists at both the individual and country levels, as well as in a micro-macro integrated framework. The main explanation for these findings - which remains to be proven by future research - is that, in institutional contexts allowing highly educated women to have large families, women of reproductive ages are more prone to make investments in both human capital and family size, because these choices are not seen as incompatible alternatives. (author's abstract)

Thesis (MMed)--Stellenbosch University, 2105. / ENGLISH ABSTRACT: Intracytoplasmic sperm injection (ICSI), as well as other micromanipulation assisted reproductive technology methods, such as physiologic ICSI (PICSI) and intracytoplasmic morphologically selected sperm injection (IMSI), are routinely used in many fertility laboratories around the world. An integral part of these methods is the manipulation of spermatozoa in preparation of the injection into the oocyte. It is common practice to place prepared spermatozoa in a viscous holding medium to facilitate the handling, manipulation and slowdown of spermatozoon movement during the immobilization and injection processes of ICSI. The possible effect of these holding mediums on basic semen parameters, as well as the sperm deoxyribonucleic acid (DNA) and structural integrity of spermatozoa, is of importance. Hamilton Thorne IVOS® developed an automated software solution for live sperm morphology evaluation under high magnification, called IMSI StrictTM. It combines Tygerberg Strict Criteria morphological classification of human spermatozoa with motile sperm organelle morphology examination (MSOME) and provides software-based categorization. The IMSI StrictTM software was developed to aid in the IMSI spermatozoon selection process that enables objective classification of spermatozoa to remove inter-technician variation. For good optics and spermatozoon evaluation in IMSI StrictTM, spermatozoa need to be moving very slowly or be immotile, but still viable. This can be achieved by placing spermatozoa in a viscous holding medium, either polyvinylpyrrolidone (PVP) or SpermSlowTM, sometimes for a substantial time period. Before marketing the clinical use of IMSI StrictTM, the possible toxicity or deleterious effect of PVP and SpermSlowTM on spermatozoa needs to be excluded. The primary objective of this study was to evaluate the effect of PVP and SpermSlowTM on human spermatozoa after different exposure times using a viability stain, CASA motility and kinetic parameters, chromatin packaging analysis (CMA3 staining analysis) and DNA fragmentation analysis (TUNEL analysis). The secondary objective was to evaluate the effect of PVP and SpermSlowTM on human spermatozoa‟s ultrastructure with Transmission Electron Microscopy. This prospective analytical study was conducted at Drs Aevitas Fertility Clinic (Vincent Pallotti Hospital, Cape Town, South Africa) as well as the Fertility Unit at Tygerberg Hospital (Cape Town, South Africa) between July 2013 and October 2014. A total of 90 separate (no duplication) semen samples were analysed for the quantitative analysis (primary objective) and 1 sample for the descriptive analysis (secondary objective). Results showed that although PVP and SpermSlowTM treated sperm outcomes often differed significantly after typical statistical analysis, clinically these two mediums were shown to be equivalent (using a specific statistical test for equivalence) for the tested outcomes. PVP and SpermSlowTM had no detrimental effect clinically on sperm viability, motility parameters, chromatin packaging and DNA fragmentation rate. The secondary investigation indicated that SpermSlowTM might exert a disintegrating effect on various sperm membranes, and as a secondary consequence of the eventual necrotic process, alteration of chromatin and cytoskeletal components. PVP medium on the other hand did not show these disintegrating effects. This finding needs to be further investigated since only one semen sample was evaluated. Based on this study‟s results, either PVP or SpermSlowTM can be used for IMSI StrictTM purposes. However, the study did not include the technical aspects of the usage of PVP and SpermSlowTM. / AFRIKAANSE OPSOMMING: Intrasitoplasmiese sperm inspuiting (ICSI), sowel as ander mikro-manipulasie voortplantings tegnieke, soos fisiologiese ICSI (PICSI) en intrasitoplasmiese morfologies geselekteerde sperm inspuiting (IMSI), word in baie fertiliteitsklinieke regoor die wêreld gebruik. 'n Integrale deel van hierdie metodes is die manipulasie van spermatosoa ter voorbereiding van die inspuitproses. Dit is algemeen om voorbereide spermatosoa in 'n viskose medium te plaas om die hantering, manipulasie en vertraging van spermatosoön beweging tydens die immobilisasie en inspuitproses van ICSI te fasiliteer. Die effek van hierdie mediums op basiese semenparameters, sowel as die sperm deoksiribonukleïensuur (DNS) en strukturele integriteit van spermatosoa, is van belang. Hamilton Thorne IVOS® het 'n sagteware oplossing, IMSI StrictTM, vir lewende sperm morfologie evaluering onder hoë vergroting ontwikkel. Hierdie sagteware bied sagteware-gebaseerde morfologiese klassifikasie deur die Tygerberg streng kriteria morfologiese klassifikasie met beweeglike spermorganel morfologie ondersoek (MSOME) te kombineer. Die IMSI StrictTM sagteware is ontwikkel om die objektiewe klassifikasie van spermatosoa vir IMSI spermatosoön seleksie moontlik te maak. Spermatosoa moet baie stadig beweeg of immotiel, maar steeds lewensvatbaar wees om goeie optika en spermatosoön evaluering vir IMSI StrictTM te verseker. Dit sal bereik kan word deur spermatosoa in 'n viskose medium, hetsy PVP (“polyvinylpyrrolidone”) of SpermSlowTM, vir 'n aansienlike tydperk te inkubeer. Voordat IMSI StrictTM vir kliniese gebruik bemark kan word moet die moontlike toksisiteit of nadelige effek van PVP en SpermSlowTM op spermatosoa uitgesluit word. Die primêre doel van hierdie studie was om die effek van PVP en SpermSlowTM op menslike spermatosoa na verskillende inkubasie tye te evalueer deur ʼn lewensvatbaarheid kleuring toets, twee sperm DNS toetse (CMA3 en TUNEL) en rekenaar geëvalueerde sperm beweeglikheid toetse te gebruik. Die sekondêre doel was om die effek van PVP en SpermSlowTM op menslike spermatosoa se ultrastruktuur deur middel van Transmissie Elektronmikroskopie te evalueer. Hierdie studie is by Drs Aevitas Fertiliteitskliniek (Vincent Pallotti Hospitaal, Kaapstad, Suid-Afrika) sowel as die Fertiliteitseenheid by Tygerberg Hospitaal (Kaapstad, Suid-Afrika) tussen Julie 2013 en Oktober 2014 uitgevoer. 'n Totaal van 90 semenmonsters vir die kwantitatiewe analise (primêre doel) en een vir die beskrywende analise (sekondêre doel) is ontleed. Resultate het getoon dat alhoewel PVP en SpermSlowTM geïnkubeerde spermuitkomste dikwels na ʼn tipiese statistiese analise betekenisvol verskil, hierdie twee mediums vir die geëvalueerde uitkomste klinies ekwivalent (bepaal deur middel van spesifieke statistiese toetse vir ekwivalensie) is. Die mediums het ook nie klinies 'n nadelige effek op sperm lewensvatbaarheid, beweeglikheid parameters, chromatien verpakking en DNS fragmentasie koers getoon nie. Die sekondêre ondersoek het getoon dat SpermSlowTM hoofsaaklik 'n effek van disintegrasie op verskeie spermmembrane getoon het. Hierdie nekrotiese proses kan lei tot verandering van chromatien en sitoskelet komponente. PVP medium het egter nie dieselfde disintegrerende effek getoon nie. Hierdie bevinding moet egter verder ondersoek word, aangesien slegs een semenmonster geëvalueer is. Alhoewel hierdie studie nie die tegniese aspekte van die gebruik van PVP en SpermSlowTM geëvalueer het nie, kan aanbeveel word dat óf PVP óf SpermSlowTM op grond van geëvalueerde uitkomste tydens die IMSI StrictTM sperm seleksie proses gebruik word.

Thesis (PhD)--Stellenbosch University, 2003. / 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. / AFRIKAANSE OPSOMMING: HOOFSTUK 1 bestaan uit ’n omvattende agtergrondstudie wat bestaan uit die ontwikkeling van diagnostiese toetse, die hantering van die egpaar in die reproduktiewe ondersteunings-program asook op die kliniese belang van spermmorfologie. Die toenemende behoefte aan die implementering van die fisiologies-geinduseerde akrosoomreaksie, as ’n belangrike bydrae tot die reproduktiewe ondersteuningsprogram, word ook beklemtoon. Die zona pellucida geinduseerde akrosoomreaksie (ZIAR), sperm-zonabinding asook rekenaar-bemiddelde semenanalises is ondersoek. HOOFSTUK 2 dek gedetailleerde eksperimentele protokolle van die materiale en metodes wat in die studie gebruik is. HOOFSTUKKE 3-6 behandel die eksperimentele navorsing wat in die laboratorium van die reproduktiewe biologie-eenheid te Tygerberg hospitaal uitgevoer is en wat as ses afsonderlike wetenskaplike publikasies aangebied word. Die doel van die eerste studie was om die regulerende rol van Gi-proteiene tydens die AR van normale spermdonors asook die rol van intakte akrosome tydens sperm-zonabinding te evalueer. Dit kom voor asof Gj-protei'ene in spermatozoa ’n belangrike regulerende rol in die ZIAR speel. Dit beklemtoon die belangrikheid van intakte akrosome tydens sperm-zonabinding. Die doel van die tweede studie was om die verhouding tussen die ZIAR en die persentasie normale spermatozoa asook die sperm-zonabindingspotensiaal tussen mans wat vir ’n roetine semenanalise verwys is te evalueer. ZIAR-toetsing moet deel uitmaak van die tweede vlak van manlike fertiliteitsondersoeke, d.w.s. funksionele toetsing, aangesien 15% van die andrologie pasiente ’n verswakte AR respons tot opgeloste ZP openbaar. In die derde studie was die doel om die moontlike verhoudinge tussen sperm-morfologie, die ZIAR en die sperm-zonabindingspotensiaal onder opeenvolgende andrologie-pasiente asook lukraak geselekteerde IVB-pasiente te evalueer. Die ZIAR-resultate bied verdere informasie aangaande disfunksionele spermatozoa en kan gebruik word as ’n addisionele diagnostiese toets aangesien hierdie resultate mislukte bevrugting tydens IVB behandeling voorspel. Die vierde studie het ten doel gehad om veranderinge in spermmotiliteitseienskappe asook hiperaktiwiteit na die blootstelling aan opgeloste zona onder andrologiepasiente te evalueer. Daar is afgelei dat opgeloste menslike zona hiperaktiwiteit induseer in spermpopulasies wat onder gunstige laboratoriumkondisies gekapasiteer is. Die gekapasiteerde spermatozoa het ’n verhoogde persentasie gehiperaktiveerde spermatozoa getoon wat met die persentasie normale spermatozoa in die ejakulaat korreleer. In HOOFSTUK 7 word aangetoon dat dit noodsaaklik is om die diagnostiese skedule by die hantering van die onvrugbare egpaar te gebruik asook dat die ontwikkeling van die funksionele toestand belangrik is vir die bepaling van ZIAR.

published_or_final_version / Community Medicine / Master / Master of Public Health

Gender norms shape our sexual experiences because they provide us with information about the appropriate behavior for men and women in social interactions (Allgeier and McCormick, 1983). Family is one of the places where we first learn about gender norms. Research on youth sexuality shows the importance of family on the sexuality of individuals through paths such as parent-child communication, parents‟ gender attitudes, parental surveillance, etc. However, less is known about other practices in the family, such as gender dynamics, or gender role practices, that could also affect the sexuality of young individuals. The aim of this dissertation is to analyze whether the sexual division of decision-making power and labor (gender dynamics) in which vii youngsters were raised, have any effect on their age at sexual debut, and their use of condoms as a contraceptive method. The source of information is the National Survey of Youth 2000 for Mexico. A discrete time hazard model is used in the analysis of age at sexual debut and a logistic regression was performed to analyze condom use. Results show that egalitarian gender dynamics have effects that differ by socioeconomic status and gender. The most remarkable findings are that shared decision-making power decreases the likelihood of an early sexual debut among girls with low socioeconomic status, and increases the likelihood of condom use among girls with high socioeconomic status. / text