INTERPRETING HIV SEROPREVALENCE DATA FROM PREGNANT-WOMEN

HIV prevalence estimates for pregnant women from unlinked anonymous su rveys are becoming increasingly available and can be used to determine the prevalence of HIV in women in the same population. The ratio of p revalence in pregnant women to that in all women is influenced by HIV- related risk behaviours that are different for pregnant and nonpregnan t women and also by differences in fertility level among infected and uninfected women. This ratio is affected by biases that are likely to be culturally and socially specific. A model is proposed for the quali fication and quantification of these biases and hence the estimation o f general female population prevalence from serosurveillance data on p regnant women.