title: Heterosexual behavior during pregnancy and perinatal transmission of HIV-1. New York City Perinatal HIV Transmission Collaborative Study Group.
abstract: OBJECTIVE
  To determine the relationship between maternal heterosexual activity during pregnancy and perinatal transmission of HIV-1.
  
  
  METHODS
  A retrospective analysis of 175 New York City HIV-1-seropositive women enrolled during pregnancy or immediately post-partum from 1986 to 1994 in a prospective cohort study.
  
  
  METHODS
  Frequency of heterosexual intercourse and condom use during pregnancy was determined from self-report measures. Unprotected intercourse was defined as follows: 'none', consistent condom use or abstinence; 'moderate', inconsistent condom use and fewer than 80 episodes of intercourse; and 'high', inconsistent condom use and 80 or more episodes.
  
  
  RESULTS
  The rate of perinatal HIV-1 transmission was 9.1% (four out of 44) among women with no unprotected intercourse during pregnancy, 22.2% (20 out of 90) among those with moderate frequency, and 39.0% (16 out of 41) among those with high frequency (P < 0.01). The relative risk (RR) of perinatal transmission was higher among women with moderate [RR, 2.4; 95% confidence interval (Cl), 0.9-6.7] and high frequency of unprotected sexual intercourse (RR, 4.3; 95% Cl, 1.6-11.8) compared with women with no unprotected sexual intercourse. When potential covariates (maternal injecting drug use, CD4 lymphocyte count, AIDS, zidovudine use, pelvic inflammatory disease or sexually transmitted disease during pregnancy, delivery mode, and extreme prematurity) were included in a logistic regression model (n = 128), the rate of perinatal transmission remained significantly higher among women with any unprotected sexual intercourse during pregnancy.
  
  
  CONCLUSIONS
  Data suggest that unprotected sexual intercourse during pregnancy influences perinatal HIV-1 transmission.
authors.affiliation: Medical and Health Research Association of New York City, Inc., New York, USA.
authors.forename: P B
authors.initials: PB
authors.lastname: Matheson
authors.forename: P A
authors.initials: PA
authors.lastname: Thomas
authors.forename: E J
authors.initials: EJ
authors.lastname: Abrams
authors.forename: V
authors.initials: V
authors.lastname: Pliner
authors.forename: G
authors.initials: G
authors.lastname: Lambert
authors.forename: M
authors.initials: M
authors.lastname: Bamji
authors.forename: K
authors.initials: K
authors.lastname: Krasinski
authors.forename: R
authors.initials: R
authors.lastname: Steketee
authors.forename: M A
authors.initials: MA
authors.lastname: Chiasson
authors.forename: D M
authors.initials: DM
authors.lastname: Thea
mesh_terms: D015982:Bias; D003075:Coitus; D017280:Condoms / Q000706:statistics & numerical data; D005260:Female; D015658:HIV Infections / Q000453:epidemiology / Q000503:physiopathology / Q000635:transmission*; D006801:Humans; D018445:Infectious Disease Transmission, Vertical; D009519:New York City / Q000453:epidemiology; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious; D012725:Sexual Behavior; D012747:Sexual Partners