Overall, STEP project findings indicate that in 1996, 79% of HIV-infected women giving birth in four states had been identified as infected by the time of their delivery (numerator based on state surveillance data; denominator based on newborn data from survey of childbearing women).
Findings from an enhanced version of the SCBW, which tested blood spots for ZDV, include the following: (1) the prevalence of ZDV use among childbearing women in the eight study states increased substantially between 1994 and 1995, indicating that treatment was widely adopted soon after it was recommended in 1994; (2) on average, in 1995, more than half of all HIV-positive women giving birth in the eight survey states received perinatal treatment with ZDV during labor/delivery or the newborn period (this is a minimum estimate because only ZDV intrapartum or postpartum was measured); (3) if the transmission rate in women receiving ZDV was reduced from 25% to 8% (as in ACTG 076), more than 150 perinatal HIV infections were prevented in these eight states alone in 1995. Population-based pediatric HIV surveillance data from 29 reporting states for 1993 to 1996 shed further light on the extent to which ZDV is being accepted and received among mothers who were diagnosed as HIV-positive before giving birth. These data show that between 1994 and 1996, the proportion of prenatally diagnosed mother–infant pairs receiving some part of the ACTG 076 regimen increased from 36% to 86%. Preliminary STEP project data based on 1995–1996 chart abstractions for approximately 500 HIV-infected women indicate that only 5% of women offered ZDV refused treatment and another 6% discontinued ZDV during pregnancy. Their reasons for discontinuing included non-compliance, toxicity/side effects, and inability to pay. Data from both the PSD study and STEP point to the conclusion that a major reason for not receiving intrapartum ZDV appears to be that the woman's status is unknown at the delivery hospital. A second reason is insufficient time to administer ZDV at the hospital. Finally, with regard to why newborns do not receive ZDV even when their mothers test positive, in preliminary data from the PSD project it appears the most common cause is that providers are not aware of the mother's test result and the second most common cause is parent refusal.
In summary, CDC representatives highlighted the following points. Since shortly after the PHS recommendations were published, there have been rapid implementation by health care providers and acceptance of therapies by HIV-infected women, as borne out in several different surveillance studies. This, in turn, has affected perinatal AIDS transmission. Overall, approximately two-thirds of pregnant HIV-infected women are on the ACTG 076 regimen. Among those