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Revised; Originally Published: 2006 / 5 pp.

An increasing number of women delay childbearing and consequently face infertility and pregnancy complications associated with age. The central contributor to compromised reproductive performance is poor oocyte quality. Despite advances in assisted reproductive technologies, a strategy to overcome the damage that oocytes receive with age is yet to be identified. This work focuses on the influence of TAp73, a protein that decreases in mouse and human eggs with age, on the developmental capacity of mouse oocytes. TAp73 deficient mice were found to have fewer active mitochondria and compromised clearance of damaged material in their oocytes, possibly due to reduced mTOR-TAp73 axis signaling. These qualities were shown to contribute to low oocyte maturation rates. Additionally, TAp73 likely mediates the action of coenzyme Q10, which restores oocyte TAp73 levels and mitochondrial quality in aged mice. Together these findings suggest that TAp73 is a promising therapeutic target for improving oocyte function.

An increasing number of women delay childbearing and consequently face infertility and pregnancy complications associated with age. The central contributor to compromised reproductive performance is poor oocyte quality. Despite advances in assisted reproductive technologies, a strategy to overcome the damage that oocytes receive with age is yet to be identified. This work focuses on the influence of TAp73, a protein that decreases in mouse and human eggs with age, on the developmental capacity of mouse oocytes. TAp73 deficient mice were found to have fewer active mitochondria and compromised clearance of damaged material in their oocytes, possibly due to reduced mTOR-TAp73 axis signaling. These qualities were shown to contribute to low oocyte maturation rates. Additionally, TAp73 likely mediates the action of coenzyme Q10, which restores oocyte TAp73 levels and mitochondrial quality in aged mice. Together these findings suggest that TAp73 is a promising therapeutic target for improving oocyte function.

Knowledge levels of issues related to fertility, reproduction, and assisted reproductive technology (ART) are low among the general population. There have also been increasing trends for women to delay childbearing and for many individuals to turn to various forms of ART to aid reproduction. Many commentators assume the provision of information targeting fertility related issues and ART will be influential in altering women’s intentions related to delay childbearing, but there is a lack of both empirical and theoretical evidence to support this assumption. Further, suggestions for how to provide education related to fertility and ART have not yet been examined. The present study examined the applicability of the theory of planned behavior (TPB) for predicting women’s intentions to delay childbearing and whether the provision of detailed, accurate, and accessible information regarding reproduction, factors influencing fertility, and the limitations of fertility treatments would alter individual attitudes and levels of perceived control surrounding delayed childbearing. Participants received one of two informational interventions (i.e., fertility-related or alcohol-related information) then completed a questionnaire measuring the constructs of the theory of planned behavior. It was predicted that the theory of planned behavior would provide an adequate framework for examining women’s intentions to delay childbearing in that attitudes, subjective norms, and perceived control would all emerge as significant predictors of these intentions (hypothesis 1). It was also predicted that the provision of detailed, accurate and accessible information regarding reproduction, factors influencing fertility, and the limitations of fertility treatment would alter young women’s intentions to delay childbearing (hypothesis 2). Multiple regression analyses provided support for Hypothesis 1 and substantiated that TPB provides an adequate framework for examining women’s intentions to delay childbearing. Hypothesis 2 was partially supported such that the intervention groups significantly differed with respect to their delayed childbearing intentions. However, most of the women in this sample did not evidence intentions to delay childbearing into critical fertile periods. Future research is warranted to examine the theory of planned behavior’s ability to predict delayed childbearing over time, across cohorts, and amongst men, as well as the impact of improved reproductive technologies and media reports of fertility on intentions to delay childbearing.

<p>After the 2012 London Summit on Family Planning, there have been major strides in advancing the family planning agenda for low and middle-income countries worldwide. Much of the existing infrastructure and funding for family planning access is in the form of supplying free contraceptives to countries. While the average yearly value of donations since 2000 was over 170 million dollars for contraceptives procured for developing countries, an ongoing debate in the empirical literature is whether increases in contraceptive access and supply drive declines in fertility (UNFPA 2014). </p><p>This dissertation explores the fertility and behavioral effects of an increase in contraceptive supply donated to Zambia. Zambia, a high-fertility developing country, receives over 80 percent of its contraceptives from multilateral donors and aid agencies. Most contraceptives are donated and provided to women for free at government clinics (DELIVER 2015). I chose Zambia as a case study to measure the relationship between contraceptive supply and fertility because of two donor-driven events that led to an increase in both the quantity and frequency of contraceptives starting in 2008 (UNFPA 2014). Donations increased because donors and the Zambian government started a systematic method of forecasting contraceptive need on December 2007, and the Mexico City Policy was lifted in January 2009. </p><p>In Chapter 1, I investigate whether a large change in quantity and frequency of donated contraceptives affected fertility, using available data on contraceptive donations to Zambia, and birth records from the 2007 and 2013 Demographic and Health Surveys. I use a difference-in-difference framework to estimate the fertility effects of a supply chain improvement program that started in 2011, and was designed to ensure more regularity of contraceptive supply. The increase in total contraceptive supply after the Mexico City Policy was rescinded is associated with a 12 percent reduction in fertility relative to the before period, after controlling for demographic characteristics and time controls. There is evidence that a supply chain improvement program led to significant fertility declines for regions that received the program after the Mexico City Policy was rescinded. </p><p>In Chapter 2, I explore the effects of the large increase in donated contraceptives on modern contraceptive uptake. According to the 2007 and 2013 Demographic and Health Surveys, there was a dramatic increase in current use of injectables, implants, and IUDs. Simultaneously, declines occurred in usage of condoms, lactational amenorrhea method (LAM), and traditional methods. In this chapter, I estimate the effect of the increase in donations on uptake, composition of contraceptive usage, and usage of methods based on distance to contraceptive access points. The results show the post-2007 period is associated with an increase in usage of injectables and the pill among women living further away from access points. </p><p>In Chapter 3, I explore attitudes towards the contraceptive supply system, and identify areas for improvement, based on qualitative interviews with 14 experts and 61 Zambian users and non-users of contraceptives. The interviews uncover systemic barriers that prevent women from consistently accessing methods, and individual barriers that exacerbate the deficiencies in supply chain procedures. I find that 39 out of 61 women interviewed, both users and non-users, had personal experiences with stock out. The qualitative results suggest that the increase in contraceptives brought to the country after 2007 may have not contributed to as large of a decline in fertility because of bottlenecks in the supply chain, and problems in maintaining stock levels at clinics. I end the chapter with a series of four recommendations for improvements in the supply chain going forward, in light of recent commitments by the Zambian government during the 2012 London Summit on Family Planning.</p> / Dissertation

Haemoglobin and its functions in various organisms is well known; it increases the ability to obtain precious oxygen and it is crucial in aerobic performance. However, if high values of haemoglobin are always beneficial, why is there a large natural variation? This study investigated the effects of varying concentrations of haemoglobin on several stages in the lifespan of Red Junglefowl: egg production and hatching, chicken growth, haemoglobin and summit metabolism. Red Junglefowl were tested for fertility in both eggs laid and eggs hatched. The offspring were individually measured for whole blood haemoglobin concentration and tested for growth and summit metabolism. The results show that there is a difference in haemoglobin after two weeks of age and that growth differs at the same time. High Hb animals do not lay smaller nor fewer eggs than low line birds but their offspring are smaller at the same time as there is a difference in haemoglobin levels. There was also a difference in the summit metabolism between the lines, where the high line animals performed better. Importantly the increase in haemoglobin did effect the growth of the animals negatively, and this would imply that higher levels of haemoglobin is not detrimental to growth.

This study was conducted to: i) determine the effect of residual feed intake (RFI) on first parity fertility and subsequent lifetime productivity of 820 females ranked as low, medium, and high RFI in western Canada and ii) investigate the relationship between RFI measured as a heifer and re-measured as a mature cow. No significant correlations were found between RFI and fertility/productivity traits. A negative trend (P < 0.10) was observed between RFI, RFIfat and MPPAbw, however, this trend was no longer apparent when RFI was adjusted for back fat and feeding event frequency (RFIfat&activity). No significant (P < 0.05) relationship was found between heifer RFI and cow RFI. These results suggest that selection for feed efficient, low RFI heifers i) has no impact on their fertility and productivity as cows, and ii) may not lead to superior feed efficiency as a mature cow as measured by RFI and Cow DMI. / February 2017

This problem consists primarily in determining the numerical value of the leukocytes after different amounts of roentgen rays had been applied to the subjects. The Atomic Energy Commission set up a problem concerning the effects of roentgen rays on the fertility in chickens, and grants were given to two institutions to study this. The blood work in this paper was an off-shoot from one of these five fertility grants.

This thesis addresses childlessness and its aspects in selected European countries: Czech Republic, Slovakia, Hungary, Bulgaria, Estonia, the Netherlands, Sweden and Norway. The aim of this work is to discover whether there are differences between capitalist and post-socialist countries when it comes to the development of childlessness and fertility. The tools are: the analysis of fertility, the average age of mothers at childbirth and analysis of childlessness using both transversal and longitudinal indicators. The indicators used in the analysis were of the first and second category. Another aim of this thesis is to find out whether there are differences between the attitudes, opinions and values when it comes to approach to the family, the division of gender roles and children between childless respondents and respondents with children. The differentiation between sex and age groups through the use of three matrices with questions from three surveys (European Values Study, Eurobarometer and ISSP) are also investigated. The factor analysis and the method of principal components are used to reduce the number of variables. The results of the factor analysis are indexed and the indexes are then used to reveal how the differences manifest themselves in the monitored groups of respondents. The main result of...