Although unproven, vaginal cleansing with antiseptics during labour could be a practical approach to reducing the rate of transmission of HIV infection from mother to infant. Before initiating a large scale clinical trial of the antiseptic chlorhexidine, we conducted a study to assess possible toxic effects as well as beneficial outcomes in 160 women volunteers: 40 non-pregnant chlorhexidine washed, 40 pregnant not washed, 40 pregnant saline washed, and 40 pregnant chlorhexidine washed. The wash was easily administered by the nurse-midwives. The participants generally felt better after the procedure, and had no complaints or adverse reactions in the subsequent 24 hours. Bacteriologically, the procedures lowered the carriage of Group B streptococcus and Staphylococcus aureus, but did not affect the frequency of T. vaginalis detection. No clinical problems were seen, and therefore the larger clinical trial of efficacy will proceed. Results of this trial are expected in late 1995.