In recent years, increased focus has been placed on the role of intrauterine infection and inflammation in the pathogenesis of fetal brain injury leading to neurodevelopmental disorders such as cerebral palsy. At present, the mechanisms by which inflammatory processes during pregnancy cause this effect on the fetus are poorly understood. Our previous work has indicated an association between experimentally-induced intrauterine infection, increased proinflammatory cytokines, and increased white matter injury in the guinea pig fetus. In order to further elucidate the pathways by which inflammation in the maternal system or the fetal membranes leads to fetal impairment, a number of studies investigating aspects of the disease process have been performed. These studies represent a body of work encompassing novel research and results in a number of human and animal studies. Using a guinea pig model of inflammation, increased amniotic fluid proinflammatory cytokines and fetal brain injury were found after a maternal inflammatory response was initiated using endotoxin. In order to more closely monitor the fetal response to chorioamnionitis, a model using the chronically catheterized fetal ovine was carried out. This study demonstrated the adverse effects on fetal white matter after intrauterine exposure to bacterial inoculation, though the physiological parameters of the fetus were relatively stable throughout the experimental protocol, even when challenged with intermittent hypoxic episodes. The placenta is an important mediator between mother and fetus during gestation, though its role in the inflammatory process is largely undefined. Studies on the placental role in the inflammatory process were undertaken, and the limited ability of proinflammatory cytokines and endotoxin to cross the placenta are detailed herein. Neurodevelopmental disorders can be monitored in animal models in order to determine effective disease models for characterization of injury and use in therapeutic strategies. Our characterizations of postnatal behaviour in the guinea pig model using motility monitoring and spatial memory testing have shown small but significant differences in pups exposed to inflammatory processes in utero. The data presented herein contributes a breadth of knowledge to the ongoing elucidation of the pathways by which fetal brain injury occurs. Determining the pathway of damage will lead to discovery of diagnostic criteria, while determining the vulnerabilities of the developing fetus is essential in formulating therapeutic options. / Thesis (Ph.D, Anatomy & Cell Biology) -- Queen's University, 2008-03-06 20:24:03.417

Prospective epidemiological studies indicate that regular exercise during the year prior to conception reduces preeclampsia risk, whereas exercise during affects pregnancy reduces preeclampsia risk only at specific dosages, or in specific subpopulations. The risk of severe preeclampsia is increased among women who exercise for more than 270 minutes/week in early pregnancy. Physiology studies are needed to identify mechanisms through which regular exercise may influence preeclampsia risk. This dissertation examined the effects of pregnancy (30-36 weeks gestation), and regular exercise participation, on two important pathophysiological features of preeclampsia; circulating anti-angiogenic markers, represented by soluble fms-like tyrosine kinase-1 (sFlt-1) and soluble endoglin (sEng), and endothelial dysfunction. The results demonstrate that regularly exercising, pregnant non-smoking women have higher levels of serum placental growth factor (PlGF), lower levels of serum sFlt-1 and sFlt-1:PlGF, and are less likely to experience high serum sEng levels, than sedentary women. The effects of exercise on PlGF and sFlt-1:PlGF are more pronounced among women exercising less than 270 minutes/week in pregnancy. Anti-angiogenic changes that could contribute to preeclampsia were not observed immediately after short-duration, moderate-intensity exercise in the third trimester. Flow-mediated dilation (FMD) and the shear stimulus for FMD are not affected by pregnancy, however the time to peak FMD was increased in pregnancy. Regular exercise did not affect FMD or its shear stimulus in healthy pregnant or non-pregnant women. FMD and its shear stimulus were positively correlated in active, but not inactive, pregnant and non-pregnant women. Pregnancy and physical activity do not affect radial artery low flow-mediated constriction (L-FMC). L-FMC is artery dependent, occurring in the radial, but not the brachial, artery of healthy pregnant and non-pregnant women. The positive correlation between L-FMC and FMD suggests that L-FMC and FMD are not independent measurements. The results of this thesis suggest that physical activity and exercise may reduce preeclampsia risk by reducing concentrations of angiogenic markers. Although exercise participation did not affect conduit artery vascular function in healthy pregnant women, future studies should investigate the effects of exercise on vascular function in women with endothelial dysfunction, or risk factors for preeclampsia. / Thesis (Ph.D, Kinesiology & Health Studies) -- Queen's University, 2009-06-11 12:41:53.466

Pre-eclampsia (PE) is a pregnancy disorder that affects roughly 5-7% of all pregnancies and is a leading cause of both maternal and fetal/neonatal morbidity and mortality. With no present cure for the disease, researchers are interested in the lower incidence of PE observed among the cigarette smoking pregnant population. However, women who use smokeless tobacco do not experience the same decreased incidence of PE, leading to hypothesis of protection against PE from the largest combustible product of cigarette smoke, carbon monoxide (CO). Studies evaluated levels of CO in PE women and found that they were statistically lower than those of healthy pregnancy. Researchers have found CO to possess many cytoprotective and regulatory properties and specifically within the placenta, it has been found to increase perfusion pressure, decrease oxidative stress, decreases ischemia/reperfusion induced apoptosis and maintain endothelial functioning. The idea for use of CO as a possible therapeutic for PE has thus become a real possibility. This study determined CO levels in pregnant women ± smoking as well as in PE women±smoking, as to discover a possible therapeutic range for future treatments. The best correlated automated CO measurement device with blood CO levels was determined, for use in future clinical studies. This thesis also sought a possible CO delivery concentration, in order to achieve the CO levels observed in the human correlation study. A threshold level of maternal CO exposure in a murine animal model was found, for which fetal and maternal negative toxicities were not observed. The results of this thesis lend a few more pieces to the complicated puzzle involving CO and PE and offer another step toward the possibility of a therapeutic treatment/prevention using this gaseous molecule. / Thesis (Master, Anatomy & Cell Biology) -- Queen's University, 2009-09-19 08:55:06.548

Increasing obesity rates in Canadian women are at an all time high with more than 50% of Canadian women falling into one of the four overweight to obese categories. Further to this 11-21% of Canadian women who are of child-bearing age are being described as overweight or obese. Along with the increasing rates of obesity is an increase in the number of operative deliveries experienced by pregnant women in Canada. Canadian women experience cesarean section (CS) approximately 21% of the time while women in Ontario experience an even higher rate of CS (26%). While currently there are several studies examining the relationship between pre-pregnancy overweight and obesity and its association with CS, there is little research examining the relationship between excess weight gain in pregnancy and operative delivery methods. Data were collected through a retrospective chart review to examine the relationship between excess weight gain in pregnancy and operative delivery methods. Mean weight gain throughout pregnancy was measured. Data analysis was conducted using t-tests, Chi-Squared analyses and Fisher’s Exact test of significance, accepting a significance level of alpha = 0.05 with a 95% Confidence Interval of difference. The analysis conducted demonstrated no significant relationship between weight gain in pregnancy and operative delivery methods. When examining maternal weight and labour type, statistical significance was reached (p = 0.04) demonstrating increased likelihood of induction with excess weight gain in pregnancy; statistical significance was also reached with maternal age greater than 35 years and increased risk for operative delivery(p = 0.04). Further analysis demonstrated statistically significant results when examining one minute Apgar scores between the group of women with recorded weights in comparison to those women whose charts did not contain weights. The lack of findings in this study may be largely attributed to the small sample size.Important practice issues were identified. It is important that pre-pregnancy or early pregnancy weight and height be recorded on all women in hospital databases as well paper charts. Consistency in recording weight units in either pounds or kilograms is imperative. Dietary consultation is an important component of prenatal care and women who enter pregnancy overweight or obese should have immediate access to nutritional counseling. / Thesis (Master, Nursing) -- Queen's University, 2010-09-22 09:00:57.695

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Since glucose is the principal substrate used during exercise and is also the main metabolic fuel for the developing embryo and fetus, exercising during pregnancy could induce a competition for fuel between fetus and exercising muscles, perturbing glucose homeostasis. To determine if exercise during pregnancy would predispose the fetus to increased risk, pregnant rats were randomly assigned to a low (4%), moderate (12%) or high (60%) carbohydrate diet, and either rested or exercised on a rodent treadmill at a moderate (15.5 m/min) or high (24.3 m/min) intensity from day 16-21 of gestation. When food intake was controlled for in the statistical model as a covariate, the level of maternal dietary carbohydrate significantly influenced maternal liver weight, heart glycogen, insulin, amniotic fluid glucose and lactate, but not maternal plasma glucose, liver or skeletal muscle glycogens. In contrast, a restricted level of maternal dietary carbohydrate, lowered fetal weight as well as fetal plasma glucose, insulin and liver glycogen. Exercise intensity significantly altered only maternal lactate levels. The results indicate that acute exercise during pregnancy can have detrimental effects on fetal development only if carbohydrate energy is restricted. Otherwise, adequate carbohydrate in the maternal diet appears to protect the fetus.

Exercise and dietary carbohydrate restriction during pregnancy independently reduce maternal weight gain and offspring survival. It was hypothesized that the combined stress of exercise and dietary carbohydrate restriction would decrease offspring survival more than the independent effects. Within the exercise and sedentary groups pregnant rats were randomly assigned to be fed either 60%, 40%, or 20% dietary carbohydrate ad libitum. No statistical interactions were found between exercise and diet. Main effects were found for litter weight, maternal feed intake and weight gain, but not for litter size, pup birthweight, or pup survival in the first two days postpartum. Exercised rats gained less weight and ate more on a per gram body weight basis than sedentary rats. Rats fed carbohydrate restricted diets ate less and gained less weight than the rats fed 60% carbohydrate. These results demonstrate that the neonatal rat is not vulnerable to the effects of moderate maternal exercise and carbohydrate restriction during pregnancy.

Giving birth to a child can have a major impact on a woman's feelings about herself and her newborn, influencing perceptions and interactions, and having both short and long term implications. In this study the effect of an experience of labour and delivery discrepant or not discrepant with expectations on mood and level of distress postpartum were investigated. / Thirty primaparas were pretested on a Labor and Delivery Expectation scale and posttested on an Experience scale two days postpartum. Two mood measures and a Distress scale were administered at this time. The influences of formal preparation for childbirth and of personality variables on the childbirth experience and postpartum mood were also investigated. / It was found that a positive mood and low distress postpartum were related to an experience of labour and delivery better than had been expected. An experience more negative than expected resulted in low mean scores for mood with high distress levels.