Fig 3. Estimated time of seroconversion for mothers with a negative HIV test result during PMTCT but became infected during their current pregnancy, South Africa, 2011–2012.

This figure shows the results of a Kaplan-Meier (KM) time to event analysis of the time of seroconversion for 20 imputations of the weighted sample of 25,061 mothers represented by 211 sampled mothers who tested negative for HIV during this pregnancy and then became infected before they delivered their baby. Dashed lines represent the individual KM estimates for each of 20 imputations of the time of seroconversion, and the dark black line is the mean of these imputations. Median time of seroconversion was estimated to be 32.8 weeks of gestation, ranging from 31.5 to 33.6 across the imputations.