title: Factors associated with vertical HIV transmission during two different time periods: the impact of zidovudine use on clinical practice at a Brazilian reference centre.
abstract: Vertical HIV transmission rates and associated factors among mother-infant pairs cared for at a Brazilian reference centre from 1988 to 1993 (period 1), and from 1996 to 1999 (period 2) were evaluated. A total of 150 and 239 infants born to HIV+ mothers were enrolled at birth during these periods. No zidovudine prophylaxis was available in period 1. In period 2, 92.4% of the infants were exposed to zidovudine (54% started at delivery or in the post-natal period). During period 1, 25 of 129 infants were found to be infected (19.4%; 95% confidence interval [CI]=13-27) vs 20 of 232 (8.6%; 95% CI=5-13) during period 2 (P <0.01). After controlling for co-variables, this decline was due to zidovudine prophylaxis, either with complete (odds ratio [OR]=0.24; 95% CI=0.08-0.70) or incomplete (OR=0.37; 95% CI=0.17-0.81) regimens. Premature rupture of membranes (OR =3.2) and rhesus-negative blood type of the infant (OR=2.6) facilitated transmission. Although confirming the protective effect of zidovudine prophylaxis, alternative approaches aimed at pregnant women identified late are needed for this population.
authors.affiliation: Department of Pediatrics, University of São Paulo, Av Bandeirantes 3900, Campus USP, 14049-900, Ribeirão Preto, São Paulo, Brasil. mmmpinha@fmrp.usp.br
authors.forename: M M
authors.initials: MM
authors.lastname: Mussi-Pinhata
authors.forename: Cristina M
authors.initials: CM
authors.lastname: Kato
authors.forename: G
authors.initials: G
authors.lastname: Duarte
authors.forename: M C
authors.initials: MC
authors.lastname: Paschoini
authors.forename: H
authors.initials: H
authors.lastname: Bettiol
authors.forename: S M
authors.initials: SM
authors.lastname: Quintana
mesh_terms: D000293:Adolescent; D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D001938:Brazil; D001942:Breast Feeding; D015331:Cohort Studies; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000150:complications; D015658:HIV Infections / Q000188:drug therapy* / Q000635:transmission*; D006801:Humans; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control* / Q000706:statistics & numerical data; D016015:Logistic Models; D015999:Multivariate Analysis; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000188:drug therapy* / Q000821:virology; D012189:Retrospective Studies; D012203:Rh Isoimmunization; D012204:Rh-Hr Blood-Group System; D015819:Substance Abuse, Intravenous / Q000150:complications; D015215:Zidovudine / Q000627:therapeutic use*
chemical_list: D019380:Anti-HIV Agents; D012204:Rh-Hr Blood-Group System; D015215:Zidovudine