title: Loss of Innate Host Defense Following Unprotected Vaginal Sex.
abstract: BACKGROUND
  Multiple host defense mechanisms protect the female genital tract from pathogens, but the impact of sexual intercourse on defense is unknown.
  
  
  METHODS
  As part of a hypothesis-generating study, 17 women provided cervicovaginal lavage (CVL) specimens at baseline (all had abstained from sexual intercourse, masturbation, and vaginal product use for 72 hours prior to screening), 2-6 hours and 10-14 hours after vaginal intercourse with a male condom, and 2-6 hours and 10-14 hours after vaginal intercourse without a male condom (5 visits total, including the baseline visit). Vaginal pH, concentrations of immune molecules, and antimicrobial activity at postcoital visits were compared to baseline values.
  
  
  RESULTS
  Vaginal pH and the transforming growth factor β1 level increased, but human beta-defensin 2 (HBD-2), HBD-3, and interleukin 8 levels decreased after unprotected sex. Median Escherichia coli inhibitory activity in CVL specimens decreased significantly from baseline at the visit 2-6 hours after unprotected sex (63% [range, -34% to 99%] vs 5% [range, -51% to 100%]; P = .02) and remained low at the visit 10-14 hours after unprotected sex (6% [range, -19% to 92%]; P = .02). Pooled human seminal plasma enhanced E. coli growth in vitro in a dose-dependent manner and, when added to CVL samples with high anti-E. coli activity, reversed the inhibition.
  
  
  CONCLUSIONS
  Unprotected vaginal sex results in a reduction in endogenous anti-E. coli activity, which may reflect, in part, enhancement of bacterial growth by seminal plasma. This finding may contribute to the risk of E. coli vaginal colonization following sexual intercourse.
authors.affiliation: Department of Pediatrics.
authors.forename: Natasha A
authors.initials: NA
authors.lastname: Nakra
authors.affiliation: Department of Pediatrics.
authors.forename: Rebecca Pellett
authors.initials: RP
authors.lastname: Madan
authors.affiliation: Department of Pediatrics.
authors.forename: Niall
authors.initials: N
authors.lastname: Buckley
authors.affiliation: Department of Pediatrics.
authors.forename: Ashley M
authors.initials: AM
authors.lastname: Huber
authors.affiliation: Department of Pediatrics.
authors.forename: Jamie L
authors.initials: JL
authors.lastname: Freiermuth
authors.affiliation: Department of Medicine, Albert Einstein College of Medicine, Bronx, New York.
authors.forename: Lilia
authors.initials: L
authors.lastname: Espinoza
authors.affiliation: Department of Medicine, Albert Einstein College of Medicine, Bronx, New York.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Walsh
authors.affiliation: Department of Medicine, University of Pittsburgh, Pennsylvania.
authors.forename: Urvi M
authors.initials: UM
authors.lastname: Parikh
authors.affiliation: Department of Medicine, University of Pittsburgh, Pennsylvania.
authors.forename: Kerri J
authors.initials: KJ
authors.lastname: Penrose
authors.affiliation: Department of Medicine, Albert Einstein College of Medicine, Bronx, New York.
authors.forename: Marla J
authors.initials: MJ
authors.lastname: Keller
authors.affiliation: Department of Pediatrics.
authors.forename: Betsy C
authors.initials: BC
authors.lastname: Herold
mesh_terms: D000328:Adult; D017280:Condoms; D005260:Female; D005786:Gene Expression Regulation / Q000276:immunology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007113:Immunity, Innate / Q000502:physiology*; D018928:Immunity, Mucosal / Q000502:physiology*; D008297:Male; D047568:Unsafe Sex; D014621:Vagina / Q000737:chemistry / Q000378:metabolism; D055815:Young Adult
keywords: E. coli; female genital tract; human beta defensins; mucosal immunity; semen; sexual intercourse