6 mg 24 to 48 hours postdelivery); or a short oral zidovudine plus lamivudine regimen (mother: zidovudine 600 mg, then 300 mg every 3 hours during labour, followed by 300 mg b. i. d. for 7 days postdelivery plus lamivudine 150 mg b. i. d. during labour and for 7 days postdelivery; infant: zidovudine 12 mg b. i. d. plus lamivudine 6 mg b. i. d. for 7 days [if infant weight < 2 kg, zidovudine 4 mg/ kg b. i. d. plus lamivudine 2 mg/ kg b. i. d. for 7 days]).