Estimating HIV prevalence in the general female population in the UK using data from pregnant women
Globally HIV is increasing rapidly amongst women and an appreciation of the total burden of infection amongst this population group is essential for planning purposes. In GB women having live births are taken to be representative of all women. Monitoring is undertaken using samples from neonates as maternal antibodies to HIV cross the placenta prior birth. However, results may be biased as pregnant women could differ from all women in terms of HTV prevalence and those with HIV could have differential fertility than uninfected women. In this thesis, ways to improve the extrapolation of neonatal seroprevalence to all women are investigated. The application of pregnant women data to all women assumes no differential fertility between persons at varying risk of HTV infection. However, analyses showed African women have both higher HTV and fertility rates than other women. In addition, results from a literature review suggested that HIV infected women may have reduced live birth rates after diagnosis, although it was unclear whether recent advances in the therapeutic and mother to child prophylactic management for HTV infected women have affected women's desire for children. A cross-sectional questionnaire study carried out to address these questions showed a third of HTV positive women did not want children after they received their HTV diagnosis. Of this group, approximately half changed their desire for children due to improvements in HIV management. Additional analyses confirmed recent changes in childbearing patterns amongst HIV positive women were likely to have taken place and that the factor most strongly associated with desire for children was reproductive history. A model developed using results described above estimated 16,000 women were living with HIV in GB in 2002. This was more than previously estimated using a 'direct' approach, reflecting an improved methodology accounting for differences in fertility and HIV risk between pregnant and non-pregnant women.