title: 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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Universidade Federal do Rio Grande (FURG), Rio Grande, RS, Brazil.
authors.forename: Matheus Costa da
authors.initials: MC
authors.lastname: Rosa
authors.affiliation: Universidade Federal do Rio Grande (FURG), Rio Grande, RS, Brazil.
authors.forename: Rubens Caurio
authors.initials: RC
authors.lastname: Lobato
authors.affiliation: Universidade Federal do Rio Grande (FURG), Rio Grande, RS, Brazil.
authors.forename: Carla Vitola
authors.initials: CV
authors.lastname: Gonçalves
authors.affiliation: Universidade Federal do Rio Grande (FURG), Rio Grande, RS, Brazil.
authors.forename: Naylê Maria Oliveira da
authors.initials: NM
authors.lastname: Silva
authors.affiliation: Universidade Federal do Rio Grande (FURG), Rio Grande, RS, Brazil.
authors.forename: Maria Fernanda Martínez
authors.initials: MF
authors.lastname: Barral
authors.affiliation: Universidade Federal do Rio Grande (FURG), Rio Grande, RS, Brazil.
authors.forename: Ana Maria Barral de
authors.initials: AM
authors.lastname: Martinez
authors.affiliation: Universidade Federal do Rio Grande (FURG), Rio Grande, RS, Brazil. Electronic address: dahoravp@gmail.com.
authors.forename: Vanusa Pousada da
authors.initials: VP
authors.lastname: Hora
mesh_terms: D001938:Brazil / Q000453:epidemiology; D005260:Female; D015658:HIV Infections / Q000453:epidemiology / Q000517:prevention & control / Q000635:transmission*; D015497:HIV-1; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control / Q000706:statistics & numerical data*; D011247:Pregnancy; D011295:Prenatal Care; D015995:Prevalence; D012307:Risk Factors; D019562:Viral Load
keywords: Grávidas; Human immunodeficiency virus type 1; Pregnant woman; Transmissão Vertical de Infecções; Vertical infection transmission; Vírus da Imunodeficiência Humana Tipo 1