Approximately 10–15% of couples experience infertility, the inability to conceive within 12 months of unprotected intercourse. Infertility often results in substantial psychologic and economic burden and has been associated with long-term adverse health outcomes including cardiovascular disease and gynecologic cancers. As reproductive failures may occur at any point in the cascade of processes necessary for pregnancy to occur, identifying mechanisms of and risk factors for infertility is an important public health goal. Diet, a complex and multi-faceted lifestyle factor, has changed dramatically in both developed and developing nations over the last few decades and currently accounts for nearly a tenth of the global burden of disease. While many studies have examined the role of the intake of specific dietary nutrients or food groups in relation to reproduction, few studies have examined the effect of dietary patterns on reproduction, especially in women without conditions known to impact menstrual function or fertility. Compared with examining individual nutrients, dietary patterns better reflect how individuals eat, thus investigations of the health effects of dietary patterns provide more translatable evidence for designing health interventions and improving population health. The objective of this dissertation is to examine the impact of dietary patterns and food allergens, which may have increased due in part to shifting dietary patterns, on fertility in women. Examining the association between dietary patterns and reproductive hormones may help elucidate the potential mechanism of how diet relates to fertility. In study one, we used data from BioCycle, a prospective cohort of regularly-menstruating premenopausal women living in New York state, to examine the association between three dietary patterns (the Healthy Eating Index (HEI)-2010, the alternative Mediterranean diet (aMed), and the Dietary Inflammatory Index (DII)) and reproductive hormone serum concentrations and anovulation. We observed that greater adherence to each of these dietary patterns was associated with slight hormonal changes and that these changes may be associated with ovulatory function. We found that women with the greatest adherence to the HEI-2010, the aMed, or the most anti-inflammatory diet had greater risk of anovulation than those with the lowest level of adherence or the least anti-inflammatory diet (Risk Ratio (RR): 2.65, 95% Confidence Interval (CI): 2.02; 3.47; RR: 2.05, 95% CI: 1.62, 2.60; RR:1.62, 95% CI: 1.23–2.14, respectively). In study two, we used data from Snart Foraeldre (SF) and Pregnancy Study Online (PRESTO), two preconception cohorts of pregnancy planners in Denmark and North America, respectively, to evaluate the association between the same three dietary patterns assessed in study one (HEI-2010, aMed, and the DII), with the addition of the Danish Dietary Guidelines Index (DDGI), and fecundability, the per-cycle probability of conception. In both cohorts, we observed that consuming a dietary pattern lower in anti-inflammatory properties was associated with reduced fecundability. In the PRESTO cohort, we observed greater fecundability with greater adherence to the HEI-2010 or the aMed. We did not observe an appreciable association between greater adherence to the DDGI or the aMed and fecundability in SF. In study three, we used data from PRESTO to evaluate the association between food allergens and fecundability. We found no appreciable association between history of diagnosed food allergy and fecundability. Within subsets of the cohort, including among those with a BMI ≥25 kg/m2 or women born ≥1990, we observed a slight association between food allergens and reduced fecundability. In conclusion, we observed that those with greater adherence to each of the dietary patterns or to more anti-inflammatory diets had an increased risk of anovulation. Conversely, we observed that those with greater adherence to specific dietary patterns or a more anti-inflammatory diet had improved fecundability. We observed a slight association between dietary patterns and reproductive hormone levels, a potential mechanism underling the association between dietary patterns and anovulation and fecundability. We observed no appreciable association between food allergies and fecundability. These findings indicate that dietary factors likely play a role in the etiology of infertility but there may be different mechanisms, likely multifactorial and not yet understood, underlying each of these associations. / 2022-05-14T00:00:00Z

Includes bibliographical references (leaves 68-79). / South Africa has high levels of both HIV/AIDS and intimate partner violence (IPV) among women. Research on the links between HIV/AIDS and IPV show that women who experience IPV are nearly two times more likely to be HIV-positive compared to women who do not. While there is increasing evidence on HIV-positive status disclosure-related IPV, studies are unclear on whether IPV is higher among HIV-positive women.

Bibliography: p. 112-125. / Childhood asthma is believed to be a serious problem both locally and internationally. This study aimed to measure the prevalence of asthma symptoms in preschool and primary school children in Mitchells Plain, Cape Town. The seculat trend in symptom prevalences over time (1993-1997) was assessed in a sub-group of 7 to 9 years old children.

Background: Evidence on the relationship between pesticide exposure and respiratory outcomes is mostly from farm workers. In most settings, poor /rich there is limited information on non-agricultural settings, particularly in children. Objective: This study investigated the relationship between urinary concentrations of the organophosphate pesticide (OP) metabolites and asthma-related outcomes among schoolchildren in four informal settlements in the Western Cape in South Africa. Methods: This study was a longitudinal study of 590 schoolchildren, with a 12-month follow up period. A standardised questionnaire adopted from the International Study of Asthma and Allergies in Childhood (ISAAC) was administered to caregivers for child's respiratory symptoms and household characteristics. Spirometry and fractional-exhaled nitric oxide (FeNO), including a phadiatop test (atopy status) and urinary dialkyl phosphate (DAP) metabolites diethylphosphate (DEP), dimethylthiophosphate (DMTP)] were measured at baseline and follow-up. Dimethylphosphate (DMP) was measured only at baseline. Results: Mean ages of schoolchildren were (9.9 ± 0.91 years) and median DAP was 32.9 ng/ml (18.4 – 52.9 ng/ml) at baseline. Incidence proportions of new asthma outcome cases at 12- months were 2.2 % doctor diagnosed asthma, 17.8 % asthma-symptom score ≥ 2, 14.5 % forced expiratory volume 1< lower limit of normal, and 5.9 % airway inflammation across all areas. In the linear mixed and fixed effect model, no consistent patterns of increased risk of new asthma-associated outcomes at the 12-month was found. However, there was a significant increase in airway inflammation (β:2.99 (95% CI: 0.48 - 5.50) in the 3rd DEP quintile (1.9 – 3.0 ng/mL) compared to the reference quintile (1.10 ng/ml). Conclusion: DAP concentrations among school children were found to be higher than those of children in other settings. However, the study did not find consistent associations between urinary concentrations of DAP metabolites and asthma related outcomes over a 12-month follow-up period among schoolchildren. Future studies with a longer follow-up period and repeated OP pesticide biomonitoring are recommended.

No description available.

Includes bibliographical references (leaves 59-62). / Malaria and typhoid are two diseases caused by different infectious organisms. Both have symptoms and signs that are very similar, making it possible to diagnose one instead of the other. In some parts of the world these two diseases are very common and may coexist in one patient, hence making it difficult for health personnel once they have confirmed one disease, to always be aware of the possible presence of another. The patients' blood can be tested in the laboratory to confirm the presence or absence of these diseases.

Background: Many contemporary agricultural pesticides are hormonally active, but few previous studies have investigated their effect on the reproductive health and growth of pubertal boys. A previous analysis found significant differences in serum reproductive hormone levels and lower anthropometric measurements as well as non-significant lower sexual maturity ratings and testicular sizes in farm boys compared to non-farm boys from the rural Western Cape in South Africa. Methodology: This analysis included 183 out of 269 school boys residing on farms and neighbouring nonfarming areas who provided urine samples in a cross-sectional study. Measurements included a questionnaire, clinical assessment of sexual maturity development (SMD), anthropometric measurements (height, weight and body mass index (BMI)), serum reproductive hormones (including luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone and oestradiol (E2)) and urinary levels of 3 dialkyl phosphates (organophosphate pesticide metabolites) including di-ethyl, di-methyl and di-methyl triphosphate (DEP, DMP and DMTP). Results: The median (interquartile range) of age and sum dialkyl phosphates of the school boys was 12 years (9-13 years) and 68.3 ng/mL (27.9-129.5 ng/mL) respectively. There were consistent, mostly non-significant associations with some dose response relationships between urinary levels of dialkyl phosphates and adverse effects on outcomes including SMD, serum reproductive hormones and anthropometric development. The strongest results included a strong positive association and dose response found between serum oestradiol > the 50th percentile and quartiles DMTP (odd ratio and confidence interval for highest and lowest quartile: 7.4; 1.7-32.4) and between BMI <50th percentile and quartiles of DMTP (odd ratio and confidence interval for highest and lowest quartile: 3.2; 1.2-9.0). Conclusion: The results provide some preliminary evidence that organophosphate pesticides exposure could alter the reproductive hormone levels and adversely affect the body size of school boys. There was also lack of evidence of other adverse effects on reproductive development. These findings require further investigation in a larger longitudinal study with seasonal bio-monitoring for pesticides.

Background: The number of studies addressing the association between diabetes mellitus (DM) and tuberculosis (TB) in the context of sub - Saharan Africa (SSA) is limited and fewer studies have determined whether DM is associated with TB among patients attending DM c linics. We aimed to assess the prevalence of TB among a population, diagnosed and receiving treatment for DM at a primary care clinic, and to identify significant risk factors of prevalent TB cases. Methods In this cross - sectional study, adult DM patients attending an outpatient clinic at a South African township were evaluated for TB using Xpert MTB/RIF testing (Xpert) and other conventional methods - clinical symptom screening, smear microscopy, chest x - ray, and culture. Socio - demographic and biochemical information were collected using the Who's STEPwise approach to surveillance of chronic disease risk factors. Findings 451 DM patients were screened for TB. 16 DM patients were diagnosed with TB, following screening giving a prevalence rate of 3 · 55% or 35 · 48 per 1000 people [95% CI: 2 · 18 - 5 · 72]. 37 · 50% (n=6) of TB cases reported at least one clinical symptom of TB [95% CI: 17 · 34 - 63 · 11%]. 62 · 5% (n=10; 95% CI :) of TB cases were HIV - positive. In a multivariate analysis, HIV (OR : 14 · 58 , p<0 · 001) and haemoptysis (OR 24 · 48, p<0 · 001) were strongly associated with prevalent TB. Identified associations were not modified by age or gender. There were no significant differences in either fasting plasma glucose or HbA1c levels between TB and non - TB DM participants. Discussion Prevalence of TB among DM population was higher than in the general population based on national estimates, highlighting an important DM - TB association in an SSA setting. HIV as a significant risk factor for TB confirms its position as a major driver in TB epidemic overall and in T2DM patients. Two - thirds of prevalent TB cases reported no TB symptoms, suggesting further research is needed to identify more accurate TB screening strategies for DM patients, particularly in HIV - infected persons, to facilitate early detection and treatment of prevalent TB in this population group.

Includes bibliographical references. / Across the world, studies have shown that hospital mortality may be influenced by seasonal factors. Very few studies examining this phenomenon have been conducted in South Africa. This study aimed to determine whether there are seasonal patterns of mortality associated with medical causes of admission to a hospital in Cape Town, and to identify demographic risk factors and specific disease categories that are associated with increased susceptibility to seasonal mortality. Part A is the protocol that was developed for the study. It begins with a summary of key aspects of the literature review. The aim, hypotheses and objectives of the study are then described, followed by a detailed account of the study methodology, ethical issues, plans for communication of the study findings and logistics. The protocol was approved by the Research Ethics Committee at University of Cape Town. Part B is the structured literature review, in which studies describing trends in seasonal mortality, and associated risk factors and determinants of excess seasonal mortality, are discussed. International and local studies were included, in order to provide an appropriated background for this study. Part C is a presentation of the study findings in the form of a journal-ready manuscript for the South African Medical Journal. Graphs have been used to illustrate the trends in mortality for each year of the study period, and the relationship between mortality and average temperatures and precipitation. Interactions with seasonal mortality and gender, socioeconomic status, ethnicity and age-groups have also been illustrated. Results have been quantified with the calculation of mortality rate ratios with 95% confidence intervals. Patterns of mortality for circulatory, respiratory and gastrointestinal diseases, and cancer, are analysed. There is a brief discussion of the findings with suggestions for further research and public health interventions to reduce excess seasonal mortality in this setting. Part D is comprised of appendices containing relevant analyses that were not be included in the article, as well as other documents pertaining to the study. Tables and graphs have been annotated, and reference is made to these appendices in the article.

Includes abstract. / Includes bibliographical references. / South Africa as a country has a high HIV prevalence. Due to the fact that HIV transmission is predominantly heterosexual, HIV discordant couples are a high risk group for HIV. A number of HIV prevention interventions have been targeted at HIV discordant couples including HIV testing and counselling. An HIV prevention trial assessing the efficacy of daily acyclovir on HIV transmission among heterosexual HIV discordant couples was undertaken in South Africa. We conducted a before and after study with the aim of evaluating the effect of HIV counselling and condom provision on sexual behaviour of the heterosexual HIV discordant couples enrolled in this prevention trial.