Sexual and demographic risk factors for herpes simplex type 1 and 2 in women attending an antenatal clinic.

OBJECTIVE To establish risk factors for the presence of HSV-2 and HSV-1 infections in pregnant women. DESIGN, POPULATION, AND SETTING: A prospective study of 3306 women attending the antenatal department Westmead Hospital, Sydney, between June 1995 and April 1998. METHODS Women completed a self administered questionnaire to establish risk factors for the presence of HSV-2 and HSV-1. Sera were tested for antibodies to HSV-2 and HSV-1. Data were analysed using SPSS and SAS. MAIN OUTCOME MEASURES Seroprevalence of and risk factors for HSV-2 and HSV-1. RESULTS 375 (11.3% (95% CI 10.3-12.5)) women were HSV-2 antibody positive. Increasing age, Asian country of birth, lower education level, public hospital status, confirmed genital herpes, a partner with genital herpes, early age of first sex, more than one lifetime sexual partner, and previous chlamydia infection were independently associated with HSV-2 seropositivity. Of 408 women tested for HSV-1 antibodies, 323 (79.2% (95% CI 74.9-83.0)) were positive. Oral herpes, oral blisters or sores, and being HSV-2 seropositive were independently associated with HSV-1 seropositive status. When the logistic regression model was rerun without HSV-2 status, parity of two or more and one or more sexual partners in the past 3 months were significant predictors of HSV-1 seropositivity. CONCLUSIONS The presence of antibodies to HSV-2 and HSV-1 is related to a number of sexual and demographic risk factors. Public health campaigns directed at encouraging young people to delay the onset of sexual activity and reduce the number of sexual partners need to be evaluated. However, the possible availability of an HSV-2 vaccine that is able to protect over 70% of women offers the best hope for control of genital herpes.