Estimated effect of incident pregnancy on time to virologic failure among 5,494 women initiating HAART in South Africa, 2004–2009.

HR, hazard ratio; CL, confidence limit.†Both standard adjusted and weighted models accounted for the same set of covariates, namely age, ethnicity, history of smoking, employment status, active tuberculosis at study entry, calendar date at entry, WHO stage, and time-updated weight, body mass index, hemoglobin, CD4 count and percent, drug regimen, and drug adherence.‡Weighted event and person-month counts are given. Unweighted, these numbers are 688/116,884 and 69/9,918.