Evaluation of factors associated with vertical HIV-1 transmission

Abstract

Objective: To compare the prevalence and factors associated with vertical transmission of human immunodeficiency virus 1 (HIV-1) among pregnant women treated in the periods of 1998-2004 and 2005-2011 in a reference service for the care of HIV-infected patients in southern Brazil.

Methods: This was a descriptive and analytical study that used the databases of laboratories from the CD4 and STDs/AIDS Viral Load National Laboratory Network of the Brazilian Ministry of Health. HIV-1-infected pregnant women were selected after an active search for clinical information and obstetric and neonatal data from their medical records between the years of 1998 and 2011.

Results: 102 pregnant women were analyzed between 1998 and 2004 and 251 in the period between 2005 and 2011, totaling 353 children born to pregnant women with HIV-1. It was observed that the vertical transmission rate was 11.8% between 1998 and 2004 and 3.2% between 2005 and 2011 (p<0.001). The increased use of antiretroviral drugs (p=0.02), the decrease in viral load (p<0.001), and time of membrane rupture lower than 4h (p<0.001) were associated with the decrease of vertical transmission factors when comparing the two periods.

Conclusion: It was observed a decrease in the rate of vertical transmission in recent years. According to the studied variables, is suggested that the risk factors for vertical transmission of HIV-1 were absence of antiretroviral therapy, high viral load in the pregnant women, and membrane rupture time >4h.

Keywords: Grávidas; Human immunodeficiency virus type 1; Pregnant woman; Transmissão Vertical de Infecções; Vertical infection transmission; Vírus da Imunodeficiência Humana Tipo 1.