Introduction Since the beginning of the AIDS epidemics, the prevention of MTCT has imprinted the directions of the debates on women´s sexual and reproductive rights. The emphasis on the use of condom as the unique way of preventing sexual transmission, together with gender/sexual norms, has undermined women’s ability to make sense of the latest scientific knowledge on their own benefit. This paper seeks to shed light on this issue by analysing the relationship between the acquisition of up-to-date information regarding HIV prevention and the use of condom.

Methods A cross-sectional study (GENIH study) was conducted between 2013 and 2014 in São Paulo with a probabilistic sample of 975 WLHIV aged 18 to 49. We applied weighted descriptive techniques and logistic regression to identify factors associated with the knowledge of new forms of HIV prevention among WLHIV such as the relationship between viral load (VL) and HIV transmission, and with condom use.

Results Although the great majority of women have correct information on the effects of HAART on VL and CD4 count, only 35% are aware that undetectable viral load is associated with a decreased risk of sexual transmission. The knowledge that HIV transmission decreases with low VL is higher among women with higher level of education (OR=1.72), women diagnosed for at least two years (OR=1.91) and among discordant couples (OR=2.56). And, the non-use of condoms in the last sexual intercourse is higher among those who know that HIV transmission decreases with low VL and among those with HIV+ partner (OR=1.69 and 2.56, respectively), regardless level of schooling.

Conclusion Women can take advantage of up-to-date information on HIV prevention once they have it. Meaningful information is a critical piece to ensure a pleasurable and safe sexual life of WLHIV, free of constraints for not using condoms 100% of the time. Sexuality and its constraints are always changing. New challenges are placed in the fourth decade of the AIDS epidemic; some of them refer to gender and social inequalities in the access to information.