This paper explores HIV-positive women's accounts of their use and non-use of treatments for the prevention of mother-to-child transmission. In-depth interviews were conducted in 2001 with 34 HIV-positive women who were diagnosed during their childbearing years. This paper reports on the 16 women who gave birth after being diagnosed with HIV. Some women reported experiencing debilitating side-effects of antiretroviral (ARV) therapy, and all were aware that the history of HIV therapy was not one of clear, consistent and benevolent effectiveness. It was evident that women wanted the best outcomes for themselves and their babies. Women represented their role vis-a-vis their children as encompassing protection against a medical fraternity that insisted on the use of ARV and prophylaxis without acknowledging the mothers' concerns about toxicity. From the women's perspective, it made sense not to let their babies become experimental subjects when long-term effects were unknown. To maximise the benefit of ARV therapy to mothers and babies, thereby reducing the risk of vertical transmission, it is imperative to understand a woman's explanation of what therapy means to her, and advisable to presume that she wants the best for her baby. Such an approach will facilitate better communication and encourage clinicians and patients to work towards a shared goal.