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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1271

MATERNAL CARDIAC AUTONOMIC FUNCTION AND FETAL BEHAVIOUR IN HYPERTENSIVE AND OBESE PREGNANCIES

Vandermeulen, JENNIFER 17 March 2009 (has links)
Hypertension in pregnancy is associated with autonomic dysregulation whereas the effects of obesity in pregnancy on maternal cardiac autonomic function are poorly understood. Furthermore, hypertension in pregnancy is associated with placental insufficiency and fetal growth restriction, whereas obesity in pregnancy is associated with placental inflammation and macrosomia. Fetal growth restriction is associated with an increased risk for language deficits at 2-5 years of age. However, maternal cardiac autonomic function and fetal auditory processing in pregnancies complicated by hypertension compared to obesity have not been examined and are the focus of this study. Maternal short-term cardiac autonomic modulation in the supine and standing postures as well as spontaneous and auditory elicited fetal behaviours were compared in 61 mother-fetal pairs (n=20 hypertensive; n=20 overweight; n=21 normal weight comparison pregnancies) from 34 to 40 weeks gestation. Maternal cardiovascular measures included systolic arterial finger-cuff blood pressure and electrocardiographic recordings of heart rate. Spontaneous observations of fetal heart rate, body and breathing movements, muscle tone and an estimate of amniotic fluid were made. Finally, each fetus received a 2 min recording of their mother and the mother’s voice in reverse (counterbalanced over subjects). When standing (othostatic stress), all three groups of women exhibited a decrease in the average baroreflex slope, parasympathetic nervous system indicator and high frequency power compared to the supine position. In a 20 min observation of spontaneous behaviour in the maternal supine compared to the standing position, fetuses of hypertensive mothers had, on average, fewer heart rate accelerations ≥ 15 bpm while the mother was supine; fetuses in the normal weight comparison group experienced more accelerations while the mother was supine. The average number of heart rate accelerations did not change in the two maternal positions for fetuses in the obese group. Fetuses in the three groups showed differential responses to the mother’s voice played forward and backward. It was concluded that there were no differences in maternal heart rate variability measures in the group of mildly hypertensive women compared to those with obesity and the normal weight comparison group. Differential spontaneous fetal heart rate accelerations and responses to the mother’s voice among the three groups needs further study with sufficient sample size to examine behaviour as a function of gestational age. / Thesis (Master, Nursing) -- Queen's University, 2009-03-13 17:45:41.837
1272

Physical activity and postpartum functional status in primiparous women

BARBACSY-MACDONALD, IBO 30 September 2011 (has links)
Background: During the early postpartum period, new mothers commonly experience fatigue and depressive symptoms which may affect their ability to function and care for themselves and their newborn. Given the demonstrated positive effects of physical activity on mood and fatigue, the purpose of this study was to describe physical activity levels across late pregnancy and the first three months postpartum, and to determine the associations between physical activity and postpartum functional status, mood, and fatigue at 6- and 12-weeks postpartum. Design: We employed a longitudinal, descriptive study design. Prenatal classes were used to recruit women. Questionnaires containing validated measures of functional status, physical activity, mood, and fatigue were administered at baseline (pregnancy), 6- and 12-weeks postpartum. Results: The sample consisted of 73 primiparous women with a mean age of 30 (+3.7) years. The majority were married (83%), Caucasian (98%), educated (70%) and middle to upper-middle class. Women in this study were physically active, with the majority being moderately active (52%). Few women had low physical activity levels (n = 4-8) throughout the study. Household activities and walking accounted for the majority of physical activity. Women in this study reported moderate levels of fatigue, with fatigue levels decreasing over time. For most postpartum women, mood and fatigue scores improved from six to 12 weeks; however, for 26% of women, scores did not. Self-care and social/community activity subcategories of functional status were the slowest to improve. Women who were low/moderately physically active at six weeks postpartum were three times as likely to have low functional status in comparison to highly physically active women (OR 3.22, 95% CI: 1.07, 9.73). At 12-weeks women with higher mental (OR 1.33, 95% CI: 1.00, 1.79) and physical fatigue (OR 1.23, 95% CI: 1.07, 1.40) were more likely to be in the lower functional status group at 12-weeks postpartum. Conclusion: Our findings indicate that high levels of self-reported mental and physical fatigue relate to lower functional status for primiparous women at six and twelve weeks postpartum. Women who are highly physically active at six and twelve weeks postpartum are more likely to have higher functional status, but this effect is influenced by perception of both mental and physical fatigue. / Thesis (Master, Nursing) -- Queen's University, 2011-09-29 15:57:25.901
1273

Spatial analysis of pregnancy complications associated with maternal cardiovascular disease risk in Ontario

Stortz, Jessica 31 July 2012 (has links)
Aim: The aim of this study was to: 1) investigate the geographic distribution of six pregnancy complications associated with future maternal cardiovascular disease risk in the province of Ontario and 2) to identify regions where women are likely to benefit from post-partum cardiovascular disease screening, based on the development of complications during pregnancy. Rationale: Cardiovascular disease is the leading cause of death in Canadian women. Pregnancy has been likened to a cardiovascular stress test and provides an early opportunity to assess a female’s lifetime risk of cardiovascular disease. Methods: This study was a retrospective analysis of data collected for the Niday Perinatal Database, provided by the Better Outcomes Registry & Network. Crude and age-standardized cumulative incidences of six pregnancy complications, and one or more pregnancy complications, were calculated for each Public Health Unit area in Ontario. The cumulative incidence of one or more pregnancy complications for women with no previous history of cardiovascular disease or traditional cardiovascular risk factors was calculated at the Public Health Unit and census subdivision area levels. Spatial statistics were applied to locate statistically significant clusters of high cumulative incidence. Results: Crude and age-standardized cumulative incidences of each pregnancy complication and one or more pregnancy complications varied across Public Health Unit areas in Ontario. The crude cumulative incidence of one or more complications ranged from 74 to 224 cases per 1000 pregnancies. The spatial analysis identified one statistically significant cluster of high cumulative incidence at the Public Health Unit area level, spanning the Lambton, Chatham-Kent, and Windsor-Essex Health Unit areas. Seven statistically significant clusters of high cumulative incidence census subdivisions were located within the following Public Health Unit areas: Chatham-Kent, Lambton, Middlesex-London, Ottawa, Leeds, Grenville and Lanark, Renfrew County, Simcoe Muskoka, Grey Bruce, and Eastern Ontario. Conclusion: Regional variation in the cumulative incidence of six pregnancy complications associated with cardiovascular disease risk was observed in Ontario. Statistically significant clusters of high cumulative incidence of one or more of these pregnancy complications were identified. These regions in particular may benefit from post-partum screening clinics and increased awareness regarding the association between pregnancy complications and cardiovascular disease. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2012-07-27 13:56:51.945
1274

The placenta as a viral reservoir: Implications for congenital cytomegalovirus infection

Davey, Ashley Unknown Date
No description available.
1275

Shifting Focus: A Videographic Inquiry of Hope and Unplanned Pregnancy

Johnson, J. Lauren Unknown Date
No description available.
1276

Early second trimester amniotic fluid erythropoietin and pregnancy outcomes

Di Giovanni, Jessica Louise. January 2008 (has links)
The study objective was to determine whether early 2 nd trimester amniotic fluid (AF) erythropoietin (EPO) was associated with and predictive of (a) development of maternal gestational diabetes (GDM) and (b) the infant outcome parameters of (i) gestational age at birth (GAAB) assessed exclusively among spontaneous vaginal deliveries or (ii) birth weight (measured in grams and percentiles). Enzyme-linked-immunosorbent assay was used to determine the EPO concentration of 170 biobanked AF samples. Student's t-test revealed no difference between GDM and non-GDM subjects. AF EPO was not predictive of GAAB despite being significantly greater among preterm infants compared to post-term infants. In contrast, AF EPO was significantly higher among the smallest infants using both birth weight classification schemes. However, following inclusion of known covariates AF EPO was predictive of gram birth weight only. Early 2nd trimester AF EPO may emerge as a useful biomarker of fetal nutritional status and/or growth.
1277

Maternal dietary glucose restriction and its effect on amniotic fluid amino acid composition

Miniaci, Sandra A. January 1997 (has links)
Since glucose is an essential nutrient for normal fetal growth and development, the impact of reduced maternal dietary glucose supply, on amniotic fluid (amf) amino acid composition was investigated. Furthermore, this study investigated whether any resulting changes in the concentrations of amf amino acids could be predictive of fetal growth and metabolic status. Pregnant rat dams were fed isocaloric diets containing graded levels of dietary glucose (0, 12, 24 and 60%) and the amf amino acid content was analysed on gestational days (gd) 18.5 to 21.5. Carbohydrate restriction produced significant increases in the concentrations of amf isoleucine (on gd 21.5), tryptophan (on gd 18.5 and 21.5) and 3-methylhistidine (on gd 20.5 and 21.5). An interaction between diet and day of gestation modified amf taurine levels such that dams fed low carbohydrate diets showed significant increases in amf taurine as pregnancy progressed. Specific amf amino acids correlated with fetal growth parameters and fetal tissue glycogen reserves indicating the ability of amf composition to reflect fetal distress under conditions of compromised maternal nutritional status. A greater statistical predictability of amf constituents was obtained with fetal growth parameters than with fetal tissue glycogen reserves. These results suggest that amf amino acids are better predictors of fetal growth status than of fetal metabolic status.
1278

Effects of fetal cocaine and tobacco exposure on newborn information processing

Potter, Susan M. January 1996 (has links)
Approximately 10% of women use cocaine and 20% smoke cigarettes during pregnancy. Animal studies indicate that both cocaine and nicotine are neuroteratogenic agents, although findings with humans are inconsistent. Studies with human infants have been plagued by unreliable subject identification procedures, poor control over confounding factors, and invalid measures of CNS integrity. The literature on prenatal cocaine and nicotine use is reviewed and two studies are presented along with an intriguing case report. The effects of maternal prenatal cocaine use (Study 1) and two levels of cigarette smoking (Study 2) on newborn information processing ability were examined using an auditory habituation-recovery paradigm. Case-control designs were employed in which subjects were individually matched on a number of maternal and infant factors. Cocaine exposure was determined by newborn meconium analysis, urine analysis, and maternal self-report. Maternal smoking was determined by self-report and a variation of the bogus pipeline method. Fetal cocaine- and nicotine-exposure were associated with differential impairments in neonatal information processing. Cocaine-exposed newborns exhibited deficits on measures of habituation and recovery to novelty. Dose-response effects of nicotine-exposure were evident on measures of orientation and habituation, but recovery to novelty was not consistently affected. The results imply that fetal cocaine-exposure severely impairs neonatal auditory information processing ability, whereas fetal tobacco-exposure is associated with deficits in information-processing which may be secondary to impairments in arousal regulation. These auditory processing deficits may be related to the later language impairments reported in follow-up studies with cocaine-and tobacco-exposed infants. Following the two studies, a case is presented of an infant born to a woman who reported using large amounts of cocaine throughout pregnancy, although the infant's meco
1279

Knowledge and utililization of contraception amongst teenagers attending an urban Indian general practice.

Jugnundan, Prakash. January 1991 (has links)
During the six month period June to December 1990, 300 Indian teenagers attending the urban general practice of the researcher were interviewed. Data pertaining to age, sex, knowledge and utilization of contraceptives were recorded. The results showed that the majority of teenagers (57%) had a good knowledge of contraceptives. Utilization, however remained low. Most (56%) knew where their local Family Planning Clinic was, but only a small percentage (15%) attended. Recommendations directed towards implementing increased utilization of various contraceptive methods and decreasing teenage pregnancies are submitted. / Thesis (M.Med.)-University of Natal, Durban, 1991.
1280

Spot urine protein to creatinine ratio testing : new techniques for detecting proteinurra in pre-eclampsia.

January 2008 (has links)
Background: The most commonly employed screening method for proteinuria is a semi- quantitative dipstick urinalysis, but it has been shown to be inaccurate in pregnancy. New developments in the assessment of proteinuria have included the use of urinary albumin measurements. The Clinitek Microalbumin Reagent Strip (Bayer Healthcare LLC, USA) is a semi-quantitative dipstick test. It is used to measure the spot urinary microalbumin to creatinine ratio that is read using the Clinitek 50 portable urine chemistry analyzer. Aims We embarked on a pilot study to validate the Clinitek 50 system by determining the accuracy of spot urinary microalbumin to creatinine ratio dipsticks and conventional visual dipsticks (Makromed) compared to the laboratory urinary microalbumin to creatinine ratio quantification to detect significant proteinuria in normotensive and hypertensive antenatal attendees. The accuracy of spot urinary microalbumin to creatinine ratio dipsticks and conventional visual dipsticks were then compared to a 24 hour urinary protein (gold standard) to detect significant proteinuria in hypertensive disorders of pregnancy. We then determined the role of proteinuria as assessed by the diagnostic accuracy of both the 24 hour urinary protein (gold standard) and the spot urinary microalbumin to creatinine ratio dipstick, in pregnancy outcomes of these participants. Methods This was a prospective study conducted at hospitals serving the Durban Metropolitan region in South Africa. To validate the urinary microalbumin to creatinine ratio dipstick, fifteen normotensive healthy pregnant women and 11 women with new onset hypertension in pregnancy were recruited .Each women had a spot midstream urine, which was assessed for proteinuria using a semi-quantitative visual dipstick (Makromed) and analysed using the semi-quantitative urinary microalbumin to creatinine ratio dipsticks (Clinitek® Microalbumin) read on the Clinitek® 50 urine chemistry analyser. A result of 1 + on visual dipsticks and a spot urinary microalbumin to creatinine ratio UAC of > 300mg/g (33.9mg/mmol) was considered as positive for significant proteinuria. The results were compared to the laboratory quantitative measurement of the urinary microalbumin to creatinine ratio. The study group comprised 163 women presenting with newly diagnosed hypertension during pregnancy after 20 weeks of gestation, being recruited from antenatal clinics. Each participant had a spot urine sample that was tested by trained midwives for proteinuria using a semi-quantitative visual dipstick (Makromed). Participants were admitted to the ward where a spot midstream urine sample was collected and analysed using the semi-quantitative urinary microalbumin to creatinine ratio dipsticks. A 24 hour quantitative urinary protein analysis was completed. The results of the urinary microalbumin to creatinine ratio dipsticks and conventional visual dipsticks were compared to the 24 hour urinary protein (gold standard) to detect significant proteinuria. A urinary microalbumin to creatinine ratio of < 300mg/g (nil and trace on visual urine dipsticks) was considered to be a negative result. A urinary microalbumin to creatinine ratio 300 mg/g (1+ to 4+ on visual urine dipsticks) was considered to be a positive result. Urinary protein 0.3 g/24 hours was considered significant proteinuria. The outcomes of pregnancy in 2 sub-categories viz. those with and without significant proteinuria were compared using the 24 hr urinary protein measurement. A secondary analysis of outcomes of pregnancy was performed by subcategorizing the participants according to the diagnostic accuracy of the urinary microalbumin to creatinine ratio dipsticks. In the 26 patients enrolled in the initial study , the visual dipstick had a sensitivity of 25% ( 95% CI [0.04-0.64] ) and specificity of 89% ( 95% CI [0.64 -0.98]).The urinary microalbumin to creatinine ratio dipsticks had a sensitivity of 88% ( 95% CI [0.47-0.99]), specificity of 89% (95% CI [0.64-0.98]), negative predictive value (NPV) of 94% (95% CI [0.69-1.00]) and positive predictive value (PPV) of 78% (95% CI [0.40-0.96]). In the 163 patients subsequently enrolled the visual dipstick had a sensitivity of 51 % ( 95% CI [0.41-0.61]) and specificity of 91% (95% CI [0.81-0.96]) .The PPV and NPV was 89 %( 95% CI [0.77-0.95]) and 58% (95% CI [0.48-0.67]) respectively. The urinary microalbumin to creatinine ratio dipsticks had a sensitivity of 63% (95% CI [0.52-0.72]) and specificity of 81 % (95% CI [0.70-0.89]). The PPV was 82% (95% CI [0.71-0.90]) and NPV was 62% (95% CI [0.51-0.71]). Our results show that in hypertensive pregnant women, significant proteinuria determined by the quantitative 24 hour urinary protein is associated with delivery at an earlier gestational age, increased induction of labour and lower birthweights compared to the non-proteinuric hypertensives (gestational hypertension). There is also a trend towards an increased maternal morbidity and perinatal mortality. When the groups were classified into pre-eclampsia and gestational hypertension using the diagnostic accuracy of the urinary microalbumin to creatinine ratio dipsticks, there were no differences in the clinical outcomes between the false negatives and true negatives except a trend towards a higher caesarean section rate in the false negatives. Conclusion The urinary microalbumin to creatinine ratio dipstick read on the Clinitek 50 system provides a semi – quantitative result of the urinary microalbumin to creatinine ratio that has good sensitivity and specificity. Furthermore, the urinary microalbumin to creatinine ratio dipstick has a good negative predictive value and a result of < 300mg/g rules out significant proteinuria and avoids unnecessary investigations in pregnancy. Both the visual dipstick (Makromed) and the urinary microalbumin to creatinine ratio dipstick read on the Clinitek 50 system are not accurate when compared to the total 24 hour urinary protein. Differences between the urinary microalbumin to creatinine ratio and 24 hour total urinary protein may be due to the variation in the albumin fraction of the total urinary protein of pre-eclampsia, technical problems with imprecision of the assay technique and clinical causes of false positives and negatives. The improved sensitivity of the automated urinary microalbumin to creatinine ratio dipstick over the visual dipstick suggests it may be a suitable substitute for the visual dipstick in clinical practice Hypertension in pregnancy associated with significant proteinuria is associated with greater adverse maternal and fetal outcome. Outcome of pregnancy is similar when a classification of gestational hypertension is made based either on the 24 hour urinary protein or the urinary microalbumin to creatinine ratio dipstick read on the Clinitek 50 system. The urinary microalbumin to creatinine ratio dipstick is a good screening test to rule out significant proteinuria. It has the potential to improve accuracy of screening for proteinuria and enhancing safety by preventing incorrect diagnosis and unnecessary investigation. Further research is required to determine its full impact and cost effectiveness in the clinical setting. / Thesis (M.Med.)-University of KwaZulu-Natal, 2008.

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