The prevalence of learner teenage pregnancies is a winnable battle, provided the major stakeholders, namely the Departments of Education (DoE) and Health (DoH) provide joint positive efforts. The situation requires continuous effective support to the teachers that have to handle the situation of teenage pregnancies at secondary schools. In spite of the implementation of Life Orientation as a school subject, to deals with sexual behaviour, sexual health, decision making regarding sexuality, risk of pregnancy, sexually transmitted infections, including HIV and Aids the prevalence of learner teenage pregnancies at secondary schools remains high. Health care professionals should become involved by promoting and implementing preventive measures to reduce the increase in learner teenage pregnancies in collaboration with the DoE. This will achieve a situation where there is assistance and support for vulnerable learners, and teachers that are daily exposed to learner pregnancies, as well as deliveries of babies on school premises. The intervention of health care professionals will provide quality care to learners and continuous support for teachers in all provinces, not only KwaZulu-Natal (KZN). The objective of this study is to explore and describe the teachers‟ experiences regarding learner teenage pregnancies in KZN. The study is explorative, descriptive and contextual in nature. An interpretative approach was suitable to address the research aim of this qualitative research design, namely to answer the research question: “How do secondary school teachers experience teenage pregnancies and unexpected deliveries at school?” Participants were selected by purposeful sampling strategy. Data were collected through individual interviews and the data analysis followed Tesch‟s (1990) method of systematic open coding. During the data analysis themes were identified, including for instance the overall experiences with learner teenage pregnancies, experiences related to unexpected deliveries at school and recommendations to cope with teenage pregnancies and unexpected deliveries at school. The participants were all aware of the negative consequences of learner teenage pregnancies, which include leaving school, the resulting unemployability of learners who left school early and subsequent poverty and low social economic status. Recommendations aimed at stakeholders such as the DoE and Health centre on jointly supporting secondary school teachers with respect to their experiences with learner teenage pregnancies and unexpected deliveries at school. Health professionals are requested to implement campaigns and school visits to supply contraceptive services, whereas the DoE has to emphasise and ensure that teachers understand the importance of contemporary approaches when implementing the Life Orientation curriculum that explicity deals with sexuality, sexual behaviour, sexual health, decision making regarding sexuality, risk of pregnancy, sexually transmitted infections including HIV and Aids. / MCur, North-West University, Potchefstroom Campus, 2015

The prevalence of learner teenage pregnancies is a winnable battle, provided the major stakeholders, namely the Departments of Education (DoE) and Health (DoH) provide joint positive efforts. The situation requires continuous effective support to the teachers that have to handle the situation of teenage pregnancies at secondary schools. In spite of the implementation of Life Orientation as a school subject, to deals with sexual behaviour, sexual health, decision making regarding sexuality, risk of pregnancy, sexually transmitted infections, including HIV and Aids the prevalence of learner teenage pregnancies at secondary schools remains high. Health care professionals should become involved by promoting and implementing preventive measures to reduce the increase in learner teenage pregnancies in collaboration with the DoE. This will achieve a situation where there is assistance and support for vulnerable learners, and teachers that are daily exposed to learner pregnancies, as well as deliveries of babies on school premises. The intervention of health care professionals will provide quality care to learners and continuous support for teachers in all provinces, not only KwaZulu-Natal (KZN). The objective of this study is to explore and describe the teachers‟ experiences regarding learner teenage pregnancies in KZN. The study is explorative, descriptive and contextual in nature. An interpretative approach was suitable to address the research aim of this qualitative research design, namely to answer the research question: “How do secondary school teachers experience teenage pregnancies and unexpected deliveries at school?” Participants were selected by purposeful sampling strategy. Data were collected through individual interviews and the data analysis followed Tesch‟s (1990) method of systematic open coding. During the data analysis themes were identified, including for instance the overall experiences with learner teenage pregnancies, experiences related to unexpected deliveries at school and recommendations to cope with teenage pregnancies and unexpected deliveries at school. The participants were all aware of the negative consequences of learner teenage pregnancies, which include leaving school, the resulting unemployability of learners who left school early and subsequent poverty and low social economic status. Recommendations aimed at stakeholders such as the DoE and Health centre on jointly supporting secondary school teachers with respect to their experiences with learner teenage pregnancies and unexpected deliveries at school. Health professionals are requested to implement campaigns and school visits to supply contraceptive services, whereas the DoE has to emphasise and ensure that teachers understand the importance of contemporary approaches when implementing the Life Orientation curriculum that explicity deals with sexuality, sexual behaviour, sexual health, decision making regarding sexuality, risk of pregnancy, sexually transmitted infections including HIV and Aids. / MCur, North-West University, Potchefstroom Campus, 2015

Digitized using a Konica Minolta 211 PCL Scanner. 300dpi (OCR). / Thesis (MA (Psychology))--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: Most portrayals in the media, research and clinical literature of teenage pregnancy and motherhood concentrate on the negative consequences for the teenager, the baby and society. Although these portrayals do capture the experience of some of the cases, they fail to grasp the complexity of these teenagers' life choices and the alternative positive impact teenage pregnancy and motherhood may have on their lives. This qualitative study focuses on the autobiographical narrative of the teenager as she experiences pregnancy and becomes a mother. The sample consists of eight participants from a rural community outside Stellenbosch, South Africa. One pre-birth interview as well as three interviews after the birth of the baby were audio taped and transcribed. Responses showed significant data with regards to the impact of the emotional experience of teenage pregnancy and motherhood on the teenager, as well as her experience of herself, changes in her life as well as the nature of the pregnancy and motherhood experience. To date, the literature does not account for the unique and individual nature of how teenage pregnancy and motherhood impacts the individual. In contrast, this research illustrates the changes in the thoughts, emotions and behaviours of teenagers when they become mothers. / AFRIKAANSE OPSOMMING: Die meeste uitbeeldings in die media, navorsing en kliniese literatuur met betrekking tot tiener swangerskap en moederskap fokus op die negatiewe gevolge vir die tiener, die baba en die samelewing. Alhoewel hierdie uitbeeldings tog die ervaringe van sekere van die gevalle verteenwoordig, misluk dit om die kompleksiteit van die tieners se lewenskeuses vas te vang, asook die alternatiewe positiewe impak wat tiener swangerskap en moederskap op hulle lewens kan hê. Hierdie kwalitatiewe studie fokus op die outobiografiese naratiewe van die tieners soos hulle swangerskap en moederskap ervaar. Die deelnemers bestaan uit agt tieners vanuit 'n plaasgemeenskap buite Stellenbosch, Suid-Afrika. Een onderhoud tydens die tiener se swangerskap sowel as drie onderhoude na die geboorte van die baba is opgeneem en getranskribeer. Betekenisvolle data ten opsigte van die impak van die emosionele ervaring van tiener swangerskap en moederskap, asook die tiener se ervaring van haarself, veranderinge in haar lewensstyl en die aard van die swangerskap en moederskap ervaring het duidelik na vore gekom in die onderhoude. Tot op hede neem die literatuur nie die unieke en individuele aard van hoe tiener swangerskap en moederskap die individu beinvloed, in ag nie. In teenstelling illustreer hierdie navorsing die veranderinge in die denke, emosies en optrede van die tieners soos hulle moeders word.

This study utilized a qualitative research methodology to examine the perspectives of six subjects, three married couples, choosing abortion to terminate unwanted pregnancies. The subjects were interviewed a few days after the abortion and six weeks after the abortion for a total of 12 hours. The researcher transcribed the interviews and observer's comments written throughout the interview process. The data were qualitatively analyzed to gain an understanding of (a) the factors which contributed to the unwanted pregnancies; (b) the process by which the couples Chose abortion to terminate the unwanted pregancies, (c) factors which contributed to the decision; (d) factors surrounding the abortion procedure; and (e) factors which predisposed the couples to different kinds of post-abortion reactions. This analysis indicated that inconsistent birth control usage was but one factor in the unwanted pregnancy. decision to abort the unwanted pregnancy created relationship conflicts because each subject had different ideas and needs in regard to managing the unwanted pregnancy. Although all of the subjects expressed relief after the abortion procedure was completed, they also expressed feelings such as guilt, sadness, and a sense of loss. All of the couples in the study experienced relationship stress, and discussed relationship issues in the interviews. More concern was verbalized about the relationship than the abortion for the couples in the study. Two of the couples expressed a commitment to making personal changes to improve the marital relationship. For the married couples in this study, the decision to terminate the unwanted pregnancy and abortion mirrored the decision-making and conflict resolution process utilized by the couples in other situations.

Orientador: Márcia Guimarães da Silva / Banca: Rodrigo Paupéro de Camargo Soares / Banca: Vera Lúcia Mores Rall / Não disponível / Abstract: Microbial invasion of the amniotic cavity has been described in term deliveries and its role on the immune modulation is of interest to the better understanding of the underlying labor processes. The aim of this study was to determine the prevalence of Mycoplasma hominis and Ureaplasma urealyticum in the amniotic fluid of term pregnancies and to evaluate its influence on cytokines production at the end of pregnancy. A cross sectional study was conducted with fifty five pregnant women out of labor with intact membranes and gestational age between 37 and 41 weeks seen at the Bom Jesus hospital in Ariquemes, Rondônia, between June 2009 and May 2010. Amniotic fluid samples and fragments of chorioamniotic membranes were collected at cesarean section. M. hominis and U. urealyticum detection was performed by PCR and Interleukin (IL)-1β, IL-6, IL-8, IL-10 and Tumor Necrosis Factor (TNF)- levels were determined by ELISA. Chorioamniotic membranes were submitted to histopatological analyses. Presence of M. hominis was detected in 36.4% of amniotic fluid samples and any of them was positive for U. urealyticum. Regarding cytokines levels, 63.6% and 90.9% of samples have not shown detectable concentrations of TNF- and IL-1β. The median concentration of IL-6 and IL-8 were 107.9 pg/mL (0-517.1) and 208.1 pg/mL (0-1897.4), respectively. Interleukin-1, IL-6, IL-8 and TNF- concentrations were not associated with the presence of M. hominis in amniotic fluid, regardless the gestational age. No sample had detectable IL-10 levels. The histopatological analyses have shown no chorioamnionitis in any of the membranes, only a discreet mononuclear infiltration in the decidua could be observed in 40.4% of the samples. Presence of M. hominis was detected in 36.4% of amniotic fluid samples and any of them was positive for U. urealyticum. Regarding cytokines levels, 63.6% and 90.9% of samples have not... (Complete abstact click electronic access below) / Mestre

<p>This study focuses on socio-cultural issues, which affect Kavango women&rsquo / s decision to participate in the PMTCT programme. It investigates the treatment methods used by HIV-positive pregnant women for themselves and their unborn babies, neonatally, during pregnancy and after delivery, particularly in relation to the prevention of transmission of HIV. The thesis further investigates whether women choose alternative services such as traditional healers for medical attention during pregnancy, birth and post-natally. The research aims to establish and describe the role of local notions and practices concerning anti-retrovirals on the aforementioned programme. Ethnographic and thus qualitative research methods were used to gather and analyze data. I spent three months working as a nurse in two health facilities that offer PMTCT in Rundu, Kavango. I also held semi-structured and open-ended interviews, formal and informal discussions, formal and informal focus groups with nurses, community counselors, pregnant women, women who had recently given birth in the health care facility and traditional health care practitioners. In the case of the latter, I utilized narratives of healing to understand their perception of HIV/AIDS, their beliefs and practices as well as their healing methods. Furthermore, I employed other informal conversations outside the formal research participants. The study shows that there is a paucity of partner involvement and in some cases women have to first seek permission from their partner before enrolling into the programme. My research findings further indicate that women utilized various traditional herbal medicines for themselves and their babies as part of their cultural beliefs and practices. It was evident that some of these, such as Likuki, affect women&rsquo / s participation in and adherence to the protocols of the PMTCT programme. </p>

Background: Teen pregnancy is associated with an array of negative social and health related outcomes for the mother as well as the baby. The risk of becoming a parent before the age of 20 is clearly elevated for former child welfare clients. Aim: The aim of this study is therefore to investigate the elevated birth rates among female adolescent child welfare clients by examining the relationship between contraceptive behaviour and pregnancies. Method: The study was based on a set of compiled register data. The study population were all females between the ages 14 and 19 during the years 2006-2008 (n. 487 115). The study group of main interest were child welfare clients who were compared to peers in the majority population as well as international and national adoptees. Analysis was conducted with multivariate logistic regression and the observed association was controlled for maternal, socio-demographic and behavioural factors. Results: The two sub-populations of child welfare clients both had much higher rates of retrieved hormonal contraceptives compared to the majority population, the international and the national adoptees up to age 17. In the ages 18 and 19 the rates were instead lower than the majority population. The child welfare clients had a stronger association to births than all groups of comparison, which was consistent with earlier research. All findings persisted after controlling for socio-demographic, maternal and behavioural factors. Conclusion: The child welfare clients showed a specific pattern of contraceptive behaviour over the age groups which was not consistent with the groups of comparison or with the expected relationship to birth rates. This suggests that teenage births cannot unanimously be predicted by the rates of retrieved hormonal contraceptives. The results imply that other factors than those investigated in this study are more influential regarding the contraceptive behaviour of this adolescent population.

<p>This study focuses on socio-cultural issues, which affect Kavango women&rsquo / s decision to participate in the PMTCT programme. It investigates the treatment methods used by HIV-positive pregnant women for themselves and their unborn babies, neonatally, during pregnancy and after delivery, particularly in relation to the prevention of transmission of HIV. The thesis further investigates whether women choose alternative services such as traditional healers for medical attention during pregnancy, birth and post-natally. The research aims to establish and describe the role of local notions and practices concerning anti-retrovirals on the aforementioned programme. Ethnographic and thus qualitative research methods were used to gather and analyze data. I spent three months working as a nurse in two health facilities that offer PMTCT in Rundu, Kavango. I also held semi-structured and open-ended interviews, formal and informal discussions, formal and informal focus groups with nurses, community counselors, pregnant women, women who had recently given birth in the health care facility and traditional health care practitioners. In the case of the latter, I utilized narratives of healing to understand their perception of HIV/AIDS, their beliefs and practices as well as their healing methods. Furthermore, I employed other informal conversations outside the formal research participants. The study shows that there is a paucity of partner involvement and in some cases women have to first seek permission from their partner before enrolling into the programme. My research findings further indicate that women utilized various traditional herbal medicines for themselves and their babies as part of their cultural beliefs and practices. It was evident that some of these, such as Likuki, affect women&rsquo / s participation in and adherence to the protocols of the PMTCT programme. </p>

Title page, table of contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / A range of epidemiological, clinical and experimental studies have demonstrated that exposure of an embryo to a suboptimal environment in vivo or ex vivo during early embryo development is associated with altered development of cardiovascular, neuroendocrine and metabolic disorders in adult life. A number of perturbations during early embryo development result in developmental adaptations by the embryo to ensure immediate survival, whilst programming the embryo for altered fetal and placental development, resulting in the eventual onset of adult disease. It has been previously shown that maternal nutrient restriction during the periconceptional period results in a hyperactivation of the pituitary - adrenal axis and increased mean arterial blood pressure in twin but not singleton pregnancies. It was therefore the first aim of this thesis to interrogate the impact of maternal undernutrition during the periconceptional period (defined as from at least 45 days prior until 7 days after conception) on fetal and placental development during early pregnancy at - day 55 of pregnancy, which coincides with the period of maximal placental growth. In Chapter 2, it has been demonstrated that there are important relationships between maternal weight gain during the periconceptional period and feto-placental growth during the first - 55 days of pregnancy and that periconceptional undernutrition has a differential effect on these relationships in singleton and twin pregnancies. In singleton pregnancies, periconceptional undernutrition disrupts the relationship between maternal weight gain during the periconceptional period and utero-placental growth and in twin pregnancies, periconceptional undernutrition results in the emergence of an inverse relationship between maternal weight gain during early pregnancy and uteroplacental growth and in a dependence of fetal growth on placental growth. (Chapter 2) In order to investigate the origins of the physiological adaptations that lead to the development of hyperactivation of the pituitary - adrenal axis and increased mean arterial blood pressure in late gestational fetuses after exposure as an embryo to periconceptional undernutrition, we investigated the development and steroidogenic capacity of the fetal adrenal gland and development of the fetal heart and kidney at - 55 days gestation (Chapter 3 and 4). The relative weight of the fetal adrenal and adrenal IGF-1, IGF-1 R, IGF-2, IGF-2R and CYP 17 mRNA expression were lower in twin compared to singleton fetuses. There was evidence that in control singletons, IGF-2R expression plays an important role in the regulation of adrenal growth and CYP 17 mRNA expression during early pregnancy. In control twins, however, whilst there was a significant positive relationship between adrenal CYP 17 and IGF-2 mRNA expression, adrenal weight was directly related to the level of adrenal IGF-1 mRNA expression. There was no effect of periconceptional undernutrition on the level of expression of any of the placental or adrenal genes in the study. In PCUN ewes, carrying singletons, however, there was a loss of the relationships between either adrenal IGF-2, IGF-2R and IGF-1 mRNA expression and adrenal growth and CYP 17 expression which were present in control singletons. Similarly in ewes carrying twins, maternal undernutrition during the periconceptional period resulted in the loss of the relationships between adrenal growth and IGF-1 expression and between _ adrenal CYP 17 and IGF-2 expression which were present in control twin fetuses. Whilst there was no effect of fetal number on fetal heart growth at - d55 in twin fetuses, there was a direct relationship between relative fetal heart and adrenal weights, which was present in both the PCUN and control groups. There was also a significant inverse relationship between maternal weight at conception and relative fetal heart weight in PCUN twin, but not PCUN singleton or control fetuses (Chapter 3). In control pregnancies maternal weight gain during the periconceptional period is inversely related to the relative weight of the fetal kidney at -55d pregnancy. In this group, relative kidney weight was also directly related to renal IGF-1 mRNA expression. In control twins maternal weight gain was inversely related to fetal kidney weight and this effect was ablated when the effects of maternal cortisol was controlled for in the analysis. In the PCUN group, whilst there was an inverse relationship between maternal weight gain during the periconceptional period and relative kidney weight, it was not possible to separate the independent effects of maternal weight loss during the periconceptional period and the subsequent weight gain during the period of refeeding. Renal IGF-1 mRNA expression was higher and renal lGF-1 R and 2R expression were lower in twin fetuses compared to singletons. After exposure to PCUN, renal IGF-1 expression was also higher than in control pregnancies independent of the fetal number (Chapter 4). Superovulation, artificial insemination, embryo transfer and in vitro embryo culture are used in a range of assisted reproductive technologies, and it has been demonstrated that varying the composition of the culture media can result in a change in pre and postnatal development. Culture of sheep embryos in media containing serum is associated with fetal overgrowth which is phenotypic of the Large Offspring Syndrome. It is not known how the combination of superovulation, artificial insemination and embryo transfer alone impacts fetoplacental development in late gestation of the sheep. There have been no studies, however, examining the differential impact of superovulation, artificial insemination and embryo transfer with or without in vitro embryo culture in the absence or presence of human serum on feto-placental development in Singleton and twin pregnancies (Chapter 5). I have therefore tested the hypothesis that superovulation, artificial insemination and embryo transfer with or without in vitro embryo culture in the presence or absence of human serum differentially alters the growth of the placenta, fetus and fetal organs during late gestation when compared to naturally conceived controls and that these effects are different in singleton and twin pregnancies. The fetal weight, CRL and abdominal circumference were significantly larger in IVCHS singleton fetuses. A novel finding in this study was lower fetal weights of twin fetuses in the ET and IVCNS groups compared to NM control twin fetuses. In addition, placental weights were lighter in twin fetuses in the ET, IVCNS and IVCHS treatment groups and this is partially due to a failure to initiate compensatory growth of placentomes in twin pregnancies (Chapter 5). The results of this thesis therefore highlight the complex interactions between the periconceptional environment (in vivo or ex vivo) and embryo or fetal number on the programming fetal and placental development. Maternal undernutrition during the periconceptional period and superovulation, artificial insemination and embryo transfer with or without in vitro culture in the absence or presence of serum alters fetal development, and I have demonstrated that these changes in fetal growth can be explained by changes in placental growth trajectory. Furthermore, a novel finding of this study is that perturbations of the periconceptional environment affect feto-placental development differently in singleton and twin pregnancies. / Thesis (Ph.D.) -- University of Adelaide, School of Molecular and Biomedical Science, 2006

Title page, table of contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / A range of epidemiological, clinical and experimental studies have demonstrated that exposure of an embryo to a suboptimal environment in vivo or ex vivo during early embryo development is associated with altered development of cardiovascular, neuroendocrine and metabolic disorders in adult life. A number of perturbations during early embryo development result in developmental adaptations by the embryo to ensure immediate survival, whilst programming the embryo for altered fetal and placental development, resulting in the eventual onset of adult disease. It has been previously shown that maternal nutrient restriction during the periconceptional period results in a hyperactivation of the pituitary - adrenal axis and increased mean arterial blood pressure in twin but not singleton pregnancies. It was therefore the first aim of this thesis to interrogate the impact of maternal undernutrition during the periconceptional period (defined as from at least 45 days prior until 7 days after conception) on fetal and placental development during early pregnancy at - day 55 of pregnancy, which coincides with the period of maximal placental growth. In Chapter 2, it has been demonstrated that there are important relationships between maternal weight gain during the periconceptional period and feto-placental growth during the first - 55 days of pregnancy and that periconceptional undernutrition has a differential effect on these relationships in singleton and twin pregnancies. In singleton pregnancies, periconceptional undernutrition disrupts the relationship between maternal weight gain during the periconceptional period and utero-placental growth and in twin pregnancies, periconceptional undernutrition results in the emergence of an inverse relationship between maternal weight gain during early pregnancy and uteroplacental growth and in a dependence of fetal growth on placental growth. (Chapter 2) In order to investigate the origins of the physiological adaptations that lead to the development of hyperactivation of the pituitary - adrenal axis and increased mean arterial blood pressure in late gestational fetuses after exposure as an embryo to periconceptional undernutrition, we investigated the development and steroidogenic capacity of the fetal adrenal gland and development of the fetal heart and kidney at - 55 days gestation (Chapter 3 and 4). The relative weight of the fetal adrenal and adrenal IGF-1, IGF-1 R, IGF-2, IGF-2R and CYP 17 mRNA expression were lower in twin compared to singleton fetuses. There was evidence that in control singletons, IGF-2R expression plays an important role in the regulation of adrenal growth and CYP 17 mRNA expression during early pregnancy. In control twins, however, whilst there was a significant positive relationship between adrenal CYP 17 and IGF-2 mRNA expression, adrenal weight was directly related to the level of adrenal IGF-1 mRNA expression. There was no effect of periconceptional undernutrition on the level of expression of any of the placental or adrenal genes in the study. In PCUN ewes, carrying singletons, however, there was a loss of the relationships between either adrenal IGF-2, IGF-2R and IGF-1 mRNA expression and adrenal growth and CYP 17 expression which were present in control singletons. Similarly in ewes carrying twins, maternal undernutrition during the periconceptional period resulted in the loss of the relationships between adrenal growth and IGF-1 expression and between _ adrenal CYP 17 and IGF-2 expression which were present in control twin fetuses. Whilst there was no effect of fetal number on fetal heart growth at - d55 in twin fetuses, there was a direct relationship between relative fetal heart and adrenal weights, which was present in both the PCUN and control groups. There was also a significant inverse relationship between maternal weight at conception and relative fetal heart weight in PCUN twin, but not PCUN singleton or control fetuses (Chapter 3). In control pregnancies maternal weight gain during the periconceptional period is inversely related to the relative weight of the fetal kidney at -55d pregnancy. In this group, relative kidney weight was also directly related to renal IGF-1 mRNA expression. In control twins maternal weight gain was inversely related to fetal kidney weight and this effect was ablated when the effects of maternal cortisol was controlled for in the analysis. In the PCUN group, whilst there was an inverse relationship between maternal weight gain during the periconceptional period and relative kidney weight, it was not possible to separate the independent effects of maternal weight loss during the periconceptional period and the subsequent weight gain during the period of refeeding. Renal IGF-1 mRNA expression was higher and renal lGF-1 R and 2R expression were lower in twin fetuses compared to singletons. After exposure to PCUN, renal IGF-1 expression was also higher than in control pregnancies independent of the fetal number (Chapter 4). Superovulation, artificial insemination, embryo transfer and in vitro embryo culture are used in a range of assisted reproductive technologies, and it has been demonstrated that varying the composition of the culture media can result in a change in pre and postnatal development. Culture of sheep embryos in media containing serum is associated with fetal overgrowth which is phenotypic of the Large Offspring Syndrome. It is not known how the combination of superovulation, artificial insemination and embryo transfer alone impacts fetoplacental development in late gestation of the sheep. There have been no studies, however, examining the differential impact of superovulation, artificial insemination and embryo transfer with or without in vitro embryo culture in the absence or presence of human serum on feto-placental development in Singleton and twin pregnancies (Chapter 5). I have therefore tested the hypothesis that superovulation, artificial insemination and embryo transfer with or without in vitro embryo culture in the presence or absence of human serum differentially alters the growth of the placenta, fetus and fetal organs during late gestation when compared to naturally conceived controls and that these effects are different in singleton and twin pregnancies. The fetal weight, CRL and abdominal circumference were significantly larger in IVCHS singleton fetuses. A novel finding in this study was lower fetal weights of twin fetuses in the ET and IVCNS groups compared to NM control twin fetuses. In addition, placental weights were lighter in twin fetuses in the ET, IVCNS and IVCHS treatment groups and this is partially due to a failure to initiate compensatory growth of placentomes in twin pregnancies (Chapter 5). The results of this thesis therefore highlight the complex interactions between the periconceptional environment (in vivo or ex vivo) and embryo or fetal number on the programming fetal and placental development. Maternal undernutrition during the periconceptional period and superovulation, artificial insemination and embryo transfer with or without in vitro culture in the absence or presence of serum alters fetal development, and I have demonstrated that these changes in fetal growth can be explained by changes in placental growth trajectory. Furthermore, a novel finding of this study is that perturbations of the periconceptional environment affect feto-placental development differently in singleton and twin pregnancies. / Thesis (Ph.D.) -- University of Adelaide, School of Molecular and Biomedical Science, 2006