We read with interest the article by Alliegro and colleagues1 on the incidence and consequences of pregnancy in women with known duration of human immunodeficiency virus (HIV) infection. In support of their findings, we have complementary data on a cohort of women in Seattle, Wash, who have been diagnosed as having HIV infection. Although we lack seroconversion dates, we were able to adjust for CD4 cell counts at the start of follow-up, as was done by Alliegro et al. Other researchers have found that after adjusting for CD4 cell counts, time since seroconversion is not statistically important in predicting the risk of disease progression.2-4