ETD Collection

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Subject: search.filters.subject.pregnancy

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Now showing 1 - 4 of 4
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    Factors associated with pregnancy in women taking part in a phase III microbocide trial in Johannesburg
    (2011-11-23) Walaza, Sibongile
    Introduction This was a secondary data analysis of a prospective cohort of women enrolled in a phase III microbicide trial between October 2005 and August 2008. The study aimed to assess the pregnancy incidence rates and factors associated with pregnancy in women using barrier method and hormonal contraception, enrolled in the trial. Methods A total of 2508 participants were enrolled in the trial and followed up for up to 12 months. Of these 2437 were included in the pregnancy incidence analysis and 2171 participants were included in the multivariate analysis. Data on the main exposure, contraception, were collected by structured interview. The main outcome of interest was pregnancy, which was measured by detection of human chorionic gonadotrophin in urine using Quick Vue® test and confirmed by laboratory based testing. The incidence rate of pregnancy was calculated as number of pregnancies per 100 women years of follow up. Kaplan Meier Survival analysis was used to determine average time to first pregnancy. Univariate and multivariate analyses were conducted using Cox regression models to asses the factors associated with incident pregnancies. Data was analysed using Stata® version 10. Results A total of 2248 women years of follow up were recorded. A total of 238 pregnancies occurred resulting in pregnancy incidence of 11 per 100 women-years of follow up (95% CI: 9.32 to 12.02). The incidence of pregnancy increased with time in the study; 98 per 100 women years of follow up (95% CI: 85.09 to 112.35) in the last 3 months compared to 2 per 100 women-years of follow up (95% CI: 0.94 to 2.92) in the first 3 months of follow up. Older age and hormonal contraception use were significantly associated with a decreased risk of pregnancy. Women 35 years and older were 49% less likely to fall pregnant compared to those who were younger than 25 years, adjusted hazard ratio (AHR) 0.51(95% CI: 0.30 to 0.88, p=0.016). Women who used hormonal contraception had a reduced risk of falling pregnant AHR 0.66(95% CI: 0.46 to 0.94, p=0.02). There was no difference between the two types of hormonal contraception (injectable vs oral) with respect to pregnancy risk. Conclusion: The incidence of pregnancy increased with time in the study. Women who used hormonal contraception and who were older were less at risk of pregnancy. There was no significant difference in pregnancy risk by type of hormonal contraception (i.e. oral contraception vs injectable contraception) used.
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    Adverse outcomes of pregnancy in Potchefstroom, South Africa
    (2010-03-02T09:41:45Z) Vundle, Ziyanda
    Introduction Adverse outcomes of pregnancy are global health problems that are much more pronounced in developing countries. The risk factors associated with adverse outcomes of pregnancy are multifactorial. In South Africa, the population prevalence and associated risk factors of maternal and perinatal mortality are routinely documented, but there are gaps in the data on other pregnancy adverse outcomes. This study was aimed at determining the prevalence rates and related risk factors of preterm births and pregnancy loss in an urban population in South Africa. Methods The study was a cross-sectional analytical community study of women 18 to 49 years of age, living in the Potchefstroom municipality. It was conducted from August 2007 to April 2008. Participants were selected using a systematic random sampling strategy; 1 210 women participated. An adapted reproductive health questionnaire was used to collect sociodemographic, environmental, occupational and reproductive health data. Results Prevalence of pregnancy loss and preterm births were estimated to be 5.6% [95% CI: 5.57% - 5.63%] and 13.4% [95% CI: 13.36% - 13.44%], respectively. Pregnancy loss was associated with psychological stress and working during pregnancy; preterm birth was associated with White, Coloured and Indian race, primary and high school education, psychological stress and chronic disease; and antenatal care use was protective against both pregnancy loss and preterm birth. Conclusion The prevalence of pregnancy loss found in this study was lower than would be expected in the general South African population; while the preterm birth prevalence, although lower than that of other developing and middle income countries, could be improved. Generally, there are common risk factors for pregnancy loss and for preterm births. Some of the existing evidence on risk factors was supported by the findings of this study. Improvement of surveillance and health information systems for pregnancy loss and preterm births would provide essential information on the burden of these outcomes in South Africa and would subsequently guide policy, research and prioritisation of effective control programmes.
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    The effect of hyperstimulation on vascular endothelial growth factor (VEGF) and cyclooxygenase 2 (COX2) in the rat uterus in early pregnancy
    (2008-09-02T08:51:29Z) Strkalj, Mirjana
    ABSTRACT Vascular permeability and angiogenesis are crucial events in the rodent and human uterus in early pregnancy and are regulated by vascular endothelial growth factor (VEGF) and prostaglandins liberated from arachidonic acid by cyclooxygenase 2 (COX2). These events coincide with the typical morphological features of the receptive uterus and are regulated by synchronized release of ovarian hormones (oestrogen and progesterone). However, administration of follicle stimulating hormone (FSH) and human chorionic gonadotropin (hCG), commonly used in assisted reproduction, affect the synchrony of the hormonal milieu, particularly by increasing oestrogen levels. This causes detrimental changes to the uterine morphology and affects vascular permeability at the site of implantation. In the present study, the expression of COX2 and VEGF was compared between control and hyperstimulated rat uteri during the peri-implantation period using immunohistochemistry and Western blot analysis. While in control pregnant rats COX2 and VEGF immunolocalization occurred in the luminal epithelial cells and stroma on consecutive days, strong immunolocalization of COX2 and VEGF occurred in the luminal epithelial cells but was inhibited in the stroma of the hyperstimulated rats. This appears to have resulted in the suppression of stromal decidualization and vascular permeability. Western blot analysis did not show any results. This may be due to low concentrations of the protein in the sample. Since vascular permeability and angiogenesis are critical to the process of implantation and are influenced by VEGF and COX2, disturbance of the pattern of these two proteins by hyperstimulation may contribute to the low implantation rate in IVF programes. immunohistochemistry and Western blot analysis. While in control pregnant rats COX2 and VEGF immunolocalization occurred in the luminal epithelial cells and stroma on consecutive days, strong immunolocalization of COX2 and VEGF occurred in the luminal epithelial cells but was inhibited in the stroma of the hyperstimulated rats. This appears to have resulted in the suppression of stromal decidualization and vascular permeability. Western blot analysis did not show any results. This may be due to low concentrations of the protein in the sample. Since vascular permeability and angiogenesis are critical to the process of implantation and are influenced by VEGF and COX2, disturbance of the pattern of these two proteins by hyperstimulation may contribute to the low implantation rate in IVF programes.
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    Experiences of pregnant adolescent girls
    (2008-03-10T14:39:25Z) Maseko, Vella
    ABSTRACT This study sought to explore the experiences of pregnant adolescent learners. It solicited information around challenges faced by pregnant adolescent girls, the impact of pregnancy on interpersonal relationships and psychological functioning, the support system that pregnant learners have, as well as their current feelings and perceptions about their experience. It is a qualitative study, and it employed thematic content analysis to analyse the results. The sample, comprising of five adolescent girls, was drawn purposively from Soweto High Schools. Adolescent pregnancy is generally perceived as a social problem because of the negative consequences often associated with it. Literature also suggests that low socio-economic circumstances and developmental factors predispose adolescents to a higher risk for unplanned pregnancy. The results of this study indicate that an experience of pregnancy during adolescence often results in challenges that may have a negative impact on normative development. Another finding is that most adolescent mothers receive very little or no financial and emotional support from families, partners or formal structures.