In humans, the frequency of meiotic segregation errors increases dramatically during female ageing. The impact of this on human reproductive health is amplified by the growing trend for women to postpone childbearing. It has long been known that the majority of meiotic segregation errors occur during the first meiotic division (MI). MI is a unique cell division involving dissolution of bivalent chromosomes formed when maternal and paternal homologs undergo reciprocal exchange of DNA and remain physically linked at chiasmata at the sites of crossover formation. Dissolution of bivalents results in dyad chromosomes consisting of two chromatids linked by centromeric cohesion. Dyads are either lost to the polar body or remain in the oocyte and realign on the metaphase II spindle, where they remain until fertilisation. My work is part of a collaborative project focussed on elucidating the molecular link between female age and chromosome segregation errors during MI. Using an aged mouse model to monitor oocyte chromosome segregation we discovered a dramatically increased incidence of anaphase defects during MI in oocytes from aged mice. This was preceded by depletion of chromosomal cohesin, which is required for cohesion between sister chromatids, thereby stabilising bivalent chromosomes. Consistent with this, single chiasmate bivalents become destabilised during female ageing. Depletion of cohesin was also associated with loss of the unified structure of sister centromeres, which is required for accurate segregation during MI. In addition, cohesin loss was associated with reduced recruitment of its protector, Sgo2. On the basis of these data, I propose that a gradual decline in chromosomal cohesin during female ageing impedes recruitment of Sgo2, which in turn may further amplify cohesin loss during prometaphase resulting in depletion of cohesin below the threshold required to maintain bivalent architecture. According to this hypothesis, cohesin depletion is sufficient to explain the age-related increase in MI errors and provides a plausible molecular mechanism for the association between female age and germ cell genomic instability.

This thesis is presented in three parts. Part one is a literature review in which the empirical literature that has investigated the determinants of condom use in adolescents is reviewed and discussed in relation to the Extended Parallel Processing Model. Part two presents the qualitative empirical paper, which explores influences on the decision making process around safe sex in young women. Part three represents a critical appraisal of the study undertaken. It contains reflections on the research process and evaluates the study in the light of good practice guidelines for qualitative research.

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Since the introduction of the combined oral contraceptive the dosage of both the oestrogen and progestogen components have been reduced to try to eliminate unwanted effects. Preparations with 20μg ethinyl oestradiol doses appear to inhibit ovulation effectively but allow appreciable ovarian activity. There have been problems also with unscheduled vaginal bleeding. Three ovulation inhibition studies were performed in which women were monitored over a pre treatment control cycle, three treatment cycles and a further cycle post treatment. Ovarian activity was monitored by ovarian ultrasound and hormone assays. Data on bleeding patterns and side effects also were recorded. The first study was a randomised double blind trial of the effect of 23 and 21 day administration of 20μg ethinyl oestradiol and 75μg gestodene. 20 women were allocated to 21 days active treatment and 22 women to receive 23 days active treatment. The women with the shorter pill free interval, had less ovarian activity in terms of serum oestradiol and follicle development. In addition there was less breakthrough bleeding. The 21 day preparation was launched in Europe in 1996.

Background: Health-seeking behaviour is a key contributor to the widespread and unfair inequalities in health outcomes related to socio-economic position. This thesis compared the levels and determinants of maternal and child health-seeking between a national sample and the rural poor in Egypt, and examined whether existing inequalities could be explained by socio-cultural characteristics or ability to afford care. Methods: This quantitative analysis relied on two datasets: the Egypt Demographic and Health Survey from 2008 and a 2010/11 survey of households below the poverty line in rural Upper Egypt. Latent variables capturing several dimensions of socio-economic position were constructed and used in multivariable regression models to predict several dimensions of maternal (antenatal and delivery care) and child (diarrhoea and acute respiratory infection) health-seeking. Results: Latent constructs capturing socio-cultural and economic resources were identified in both datasets. Two further dimensions of socio-economic position in the Upper Egypt sample included dwelling quality and woman’s status. DHS analysis showed that sociocultural and economic capital were independently positively associated with seeking antenatal and delivery care among women, and with seeking timely and private child illness treatment. Free-of-charge public maternal care was not effectively targeted to poorest women. Poor households in Upper Egypt showed lower maternal healthseeking levels than nationally; both socio-cultural and economic resourcefulness positively predicted maternal health-seeking, dwelling quality was positively associated with private provider use, while women’s status was not associated with any dimension of maternal health-seeking behaviour. Conclusion: A better understanding of perceived and objective quality of care in both public and private sectors is required to reduce existing inequalities in the coverage of essential maternal and child health interventions. Improvement in free public care targeting is required to prevent catastrophically high expenditures for basic care among poor households.

Background: The timing of first sexual intercourse has long been of public health concern and a predominant focus of research into the sexual behaviour of young people. The onset of sexual activity has most commonly been defined in terms of chronological age – with particular attention to ‘early’ sex. Arguments for a more nuanced concept of timing have been made on the grounds that age fails capture individual differences and the context of the encounter. The concept of ‘sexual competence’ was most notably first operationalised by Wellings et al. (2001) using self-reports of four variables. Participants were classified as ‘sexually competent’ at first heterosexual intercourse if they reported the following four conditions: contraceptive protection, autonomy of decision (not due to external influences such as alcohol or peer pressure), consensuality (equal willingness of both partners), and acceptable timing (that it occurred at the ‘right time’). Methods: Using data from the Third National Survey of Sexual Attitudes and Lifestyles (Natsal-3), this study used a range of methods (confirmatory factor analysis, latent class analysis, and multivariable logistic regression) to conduct a quantitative examination of the properties of, and factors associated with, the measure of sexual competence at first intercourse. Supplementary analyses using two other datasets (Avon Longitudinal Study of Parents and Children, and Dunedin Multidisciplinary Health and Development Study) were also carried out in order to examine specific research questions that emerged. Finally, in-depth interviews were conducted with a subsample of Natsal-3 respondents to explore how they formulated their answers to the survey questions used to construct the measure of sexual competence. Findings: Statistical analyses found evidence that the four components of the sexual competence measure tap into a single underlying construct, and that the measure is associated with a range factors in the directions expected. For example, sexual non-competence at first intercourse was associated with several adverse sexual health outcomes, including sexually transmitted infections, unplanned pregnancy, and low sexual function. The qualitative component of this research found that responses to the four survey questions were formulated with reference to characteristics of the self, the partner, and the relationship, as well as what happened after the event of first intercourse. Conclusions: For a rather simply constructed operationalisation of a complex concept, the measure of sexual competence at first intercourse performs well empirically. The findings presented support the concept’s further integration into public health research and practice, and add to the evidence base supporting emphasis on enabling young people to protect the physical, social, and emotional aspects of their sexual health, from the onset of sexual activity.

Background: Young people are a demographic force and their sexual and reproductive health (SRH) has become an area of focus for many national governments in both developed and developing countries. Addressing the SRH problems of young people is essential for the social and economic development of any nation and presents an opportunity for building human capital, respecting human rights and alleviating the intergeneration cycle of poverty across societies. Aim: This study aimed at firstly exploring experiences and perceptions of young people aged 10-24, community members, health service providers (HSP), programme managers and policy makers on the SRH problems of young people and available SRH services. Secondly, the study sought to explore the different models of SRH service provision and, through a stakeholder consultative process, develop an SRH service delivery model for young people in Kenya. The development of the model was also informed by findings from literature review on ASRH interventions and components of models of health service delivery. Methodology: This was a qualitative study which took a social constructionism approach. The study took place in four areas, Nairobi city and three district hospitals (Laikipia, Meru central, and Kirinyaga). Data was collected from a total of 8 health facilities, 5 integrated facilities and three youth centres, using focus group discussions (FGDs) and in-depth interviews (IDIs). 18 FGDs and 39 IDIs were conducted with young people; 10 FGDs with community members; 19 IDIs with health service providers; and 11 IDIs with facility managers and programme managers. Interviews were tape recorded and transcribed. With the assistance of NVIVO8 data was coded and analysed using the thematic framework approach. Results: Young people’s perceptions of available SRH services show variations between boys and girls with regards to the model of service delivery. Young girls seeking ANC and FP services at integrated facilities characterised the available services as good. On the contrary, boys indicated that SRH services at integrated facilities have been designed for women and children, and so they felt uncomfortable seeking services from these facilities. Apart from receiving SRH services at youth centres, young people place emphasis on the non-health benefits they personally receive from youth centres such as preventing idleness, confidence building, information gap-bridging, improving interpersonal communication skills, vocational training and facilitating career progression. Majority of community members are not aware of the SRH services available at the health facilities even in areas where youth centres are present. Community members approve of young people receiving services which they feel are educative and preventive in nature and disapprove of services which they feel encourage young people to engage in sexual activity such as promotion of contraceptives. HSP report not being competent in adolescent counselling, facing a dilemma and not being comfortable with providing SRH services to young people. HSP also report being torn between their personal feelings, cultural norms and values and respecting young people’s right to accessing SRH services. Broadly two models of SRH services are examined in this study; the integrated model and youth centres. Youth centres can either be facility-based or community-based. The findings presented in this study do not point to one single model as the best SRH service provision model as each have their own strengths and weaknesses. However, both models face implementation challenges which include: a weak monitoring and supervisory system, weak linkages with other government line ministries and departments and heavy reliance on donor funding. Specific to facility-based youth centres implementation challenges include: lack of ownership and support by district managers, being seen as parallel health structures and conflicts of interest in youth centre utilization between district managers and young people. Although the youth centre is reported as the preferred model by some young people and healthcare providers, its sustainability is not guaranteed. Moreover, the range of services it’s able to provide is limited due to deficiencies in staffing, supplies and equipments. Conclusion: Addressing the SRH problems of young people in Kenya remain a big challenge for the health sector. Although some progress has been made with regards to creating a friendly policy environment for SRH service provision, the major drawback lies in implementation of these policies. This study recommends a multi-component SRH service delivery model with six core services, a strong support structure onto which to anchor service delivery and linkages to existing government systems and processes to enhance sustainability. This is the first study to be conducted in Kenya using qualitative methodology and result in the development of a SRH service delivery model for young people after triangulation of views and experiences of young people themselves, community members, health care providers, programme managers and policy makers.

This study uses data from National Family Planning and Reproductive Health Survey undertaken in 2001, systematic reviews of provincial policy fertility in 1990s, information on the nature of family planning (FP) services at grassroots institutions and a new measure of women's son preference, to advance knowledge of determinants of reproduction in rural China. The main statistical methods in this study include latent class analysis, life table, parity progression ratio, multilevel logistic regression and multilevel Poisson regression. The analysis is performed within groups of provinces according to their population policy (I-child, 1.5-child and 2-child). The results showed that fertility rate was closely related to China's population policy: the stricter the policy, the lower the fertility rate. By the end of the last century, fertility rates for the three types of provinces were close to respective policy fertility, indicating a success of China's population policy. However, strict population policy increased risks of abortion and imbalance in sex ratio at birth (SRB), particularly the rising sex ratio of second births in 1.5-child provinces. Variations in availability of specific FP methods by local services did not play a leading role in reducing fertility level, risk of abortion and imbalanced SRB. Son preference at province or individual level had strong impacts on progression to second birth, risk of abortion, and SRB, but the effects vary between types of provinces. Effects of other individual characteristics, i.e., couples' age, women's education, sex of existing child, on reproduction are also explored and discussed in this study. It can be concluded that strict implementation of population policy was the dominant influence on fertility levels but it also raised risk of abortion and imbalance in SRB in rural China. For these and other reasons, China needs to relax its I-child and 1.5-child policies immediately.

British women experience a conundrum in the context of contraception. Despite knowledge about and free access to myriad methods Britain currently has high rates of unintended pregnancy (estimated as high as 2/3 in some cases). This thesis uses a feminist approach and Foucauldian theory to explore this phenomenon by addressing the gaps in current understanding namely the situated and subjective experiences of contraception use over the life course. Using a qualitative life history method and map-making, this research used Listening Guide analysis to understand 15 British women’s contraceptive life histories. Three substantive chapters situate these narratives within the political and social landscape of neoliberal Britain over the last 30 years. The first presents 4 individual life stories and drawing on the concept of ‘stratified reproduction’ indicates how many women’s contraceptive choice is not free but is shaped by structural inequalities. The second exposes the meaningful-ness of hormonal contraceptive ‘side effects’, namely the consequence to their sense of self, and argues for a departure from the typically reductive perspectives on the impacts of contraception use. The third chapter highlights the changes over time, or lack thereof, in contraceptive practice as experienced by the women participants and demands a shift from the rhetoric of ‘contraceptive choice’ towards a lived reality of supportive women-centred provision. Finally, these findings are conceptualised as ‘disconnections’ of a woman from both herself and from contraceptive providers and are theorised in relation to competing neoliberal (masculine) and female subjectivities. I argue that the current circumstances create an impossible position for contracepting women to successfully occupy. In conclusion, the narratives in this thesis compel us to adopt instead a model that approaches contraception use as more than an individual experience and to recognise and address the contextual factors that undermine women’s contraceptive choice and compromise sustainable use.

Background: Invasive cervical cancer (ICC) is the second most common cancer among women in developing countries where early age at first sexual intercourse (AFSI) and first pregnancy (AFP) are prevalent events. The epidemiological evidence of how these sexual and reproductive health (SRH) factors impact the natural history of human papillomavirus (HPV) and ICC remain inconclusive. It has been debated that a woman's risk for ICC will depend more on the "high-risk" sexual behaviour of the male partner than of her own behaviour. Passive smoking in the context of couples is unclear. The aim is to study SRH factors in relation to ICC risk in developing countries. Methods: Study 1 evaluated the risk of ICC and its association with AFSI and AFP in a pooled analysis of IARC case-control studies of ICC from eight developing countries. Study 2 assessed these SRH factors and risk of HPV persistence in a population-based natural history cohort study in Guanacaste, Costa Rica. Study 3 characterised the male role in the aetiology of ICC among couples in a pooled analysis of five ICC case-control studies and two cervical carcinoma in situ (CIS) case-control studies. Results: The ICC risk was 2.4-fold among those who reported AFSI and AFP :~a6 years compared with AFSI and AFP ~21 years. Decreasing AFP, not AFSI, was associated with an increased risk of a-year persistence. Lifetime number of sexual partners of the husband was the strongest predictor of CIS and ICC risk. The absence of circumcision was significantly associated with an increased risk of CIS. A 2-fold increased risk of ICC was also found among couples with both ever smoking men and women. These data confirm AFSI and AFP as risk factors for ICC, but any independent effects could not be distinguished. The association of AFP with HPV persistence suggests that AFP may play a more relevant role in cervical carcinogenesis. The combined effects of exposure to active and passive smoking suggest its potential adverse role in cervical carcinogenesis.