Figure 3 Estimated proportion of HIV infected women diagnosed before delivery*, and of exposed children becoming HIV infected†, England, 1998–2003. (*Includes previously diagnosed and those diagnosed through antenatal testing. †Assumes a vertical transmission rate of 26.5% in undiagnosed women and 2.2% in diagnosed women.¹³ ‡These data contain reports received by the end of September 2004 and are subject to reporting delay, particularly for 2003.) Data source: Unlinked Anonymous Programme and the National Study of HIV in Pregnancy and Childhood.