Oral contraceptive use and risk of vulvodynia: a population-based longitudinal study.

OBJECTIVE: To assess whether the risk of vulvodynia is associated with previous use of oral contraceptives (OCs).
DESIGN: Longitudinal population-based study.
SETTING: Four counties in south-east Michigan, USA. POPULATION: A population-based sample of women, aged 18 years and older, enrolled using random-digit dialling.
METHODS: Enrolled women completed surveys that included information on demographic characteristics, health status, current symptoms, past and present OC use, and a validated screen for vulvodynia. The temporal relationship between OC use and subsequent symptoms of vulvodynia was assessed using Cox regression, with OC exposure modelled as a time-varying covariate. MAIN OUTCOME MEASURE: Vulvodynia, as determined by validated screen.
RESULTS: Women aged <50 years who provided data on OC use, completed all questions required for the vulvodynia screen, and had first sexual intercourse prior to the onset of vulvodynia symptoms were eligible (n = 906). Of these, 71.2% (n = 645) had used OCs. The vulvodynia screen was positive in 8.2% (n = 74) for current vulvodynia and in 20.8% (n = 188) for past vulvodynia. Although crude cross-tabulation suggested that women with current or past vulvodynia were less likely to have been exposed to OCs prior to the onset of pain (60.7%), compared with those without this disorder (69.3%), the Cox regression analysis identified no association between vulvodynia and previous OC use (HR 1.08, 95% CI 0.81-1.43, P = 0.60). This null finding persisted after controlling for ethnicity, marital status, educational level, duration of use, and age at first OC use.
CONCLUSION: For women aged <50 years of age, OC use did not increase the risk of subsequent vulvodynia.