Prenatal testing and prevalence of HIV infection during pregnancy: data from the "Birth in Brazil" study, a national hospital-based study.

Background: The rate of vertical HIV transmission has decreased in Brazil, but regional inequalities suggest problems in implementing control measures during pregnancy and delivery. The aims of this study were to ascertain the coverage of HIV testing during prenatal care and estimate the prevalence of HIV infection during pregnancy in Brazil.

Methods: This was a national hospital-based study of 23,894 women that was conducted in 2011-2012. The data came from interviews with mothers during postpartum hospitalization, from hospital medical files and from prenatal cards. All the pregnant women with reactive serological results for HIV infection marked on their cards or with diagnoses of HIV infection during the hospital stay for delivery were considered cases of HIV infection. Univariate and multivariable logistic regression were performed to investigate factors associated with the prevalence of HIV infection and with performing at least one HIV test during pregnancy.

Results: Among participating women, the coverage of testing for HIV infection was 81.7% among those who presented with prenatal card and the prevalence of HIV infection among pregnant women was 0.4% (95% CI: 0.32-0.51%). In the adjusted analysis, there was higher coverage of testing among women living in the South and Southeast regions; of women aged 35 years and over; with greater schooling levels; who self-reported as white; with prenatal care provided in private services; with an early start to prenatal care; and with an adequate number of consultations, defined as a minimum of six for a term pregnancy. In the adjusted analyses there was a greater odds ratio of HIV infection among women living in the South region, aged 35 years and over, with schooling of less than 8 years, who self-reported race as black, without a partner, with syphilis coinfection and who were attended by public services.

Conclusions: The prevalence of HIV infection among pregnant women in Brazil remains below 1% and the coverage of testing for HIV infection is over 80%. However, the regional and social inequalities in access to healthcare services and the missed opportunities for diagnoses of HIV infection indicate the importance of strengthening HIV infection control programs during pregnancy.