Prevalence and correlates of HPV among women attending family-planning clinics in Thailand.

BACKGROUND: Cervical cancer is the most common cancer among women of reproductive age in Thailand. However, information on the prevalence and correlates of anogenital HPV infection in Thailand is sparse. METHODS: HPV genotype information, reproductive factors, sexual behavior, other STI and clinical information, and cervical cytology and histology were assessed at enrollment among one thousand two hundred and fifty-six (n=1,256) HIV negative women aged 20-37 from Thailand enrolled in a prospective study of the natural history of HPV. The type-specific prevalence of HPV was estimated using cervical swab specimens from healthy women and women with a diagnosis of CIN 2/3 at baseline. Prevalence ratios (95% CI) were estimated using Poisson regression to quantify the association of demographic, behavioral, and clinical correlates with prevalent HPV infection. RESULTS: Overall, 307 (24.6%) and 175 (14.0%) of women were positive for any HPV type and any HR-HPV type, respectively; the most common types were 72, 52, 62, and 16. Among women diagnosed with CIN 2/3 at enrollment (n=11), the most prevalent HPV types were 52 and 16. In multivariate analysis, HPV prevalence at enrollment was higher among women with: long-term combined oral contraceptive use, a higher number of lifetime sexual partners, a prior Chlamydia infection, and a current diagnosis of Bacterial Vaginosis. CONCLUSION: The study findings provide important information that can be used in the evaluation of primary and secondary interventions designed to reduce the burden of cervical cancer in Thailand.

Combined oral contraceptive use increases HPV persistence but not new HPV detection in a cohort of women from Thailand.

BACKGROUND: Women diagnosed with cervical cancer report longer duration and more recent use of combined oral contraceptives (COCs). It is unclear how COC use impacts risk of cervical carcinogenesis. METHODS: We estimated the risk of new human papillomavirus (HPV) DNA detection and persistence among 1135 human immunodeficiency virus (HIV)-negative women aged 20-37 years from Thailand who were followed for 18 months at 6-month intervals. Type-specific HPV DNA, demographic information, hormonal contraceptive use, sexual behavior, genital tract coinfection, and Papanicolaou test results were assessed at baseline and each follow-up. RESULTS: Women who reported current COC use during follow-up were less likely to clear HPV infection compared with nonusers, independent of sexual behavior, and Papanicolaou test diagnosis (AHR: 0.67 [95% CI: .49-.93]). Similar associations were not observed among women reporting current use of depomedroxyprogesterone acetate (DMPA). Neither COC nor DMPA use was significantly associated with new HPV DNA detection. CONCLUSIONS: These data do not support the hypothesis that contraceptive use is associated with cervical cancer risk via increased risk of HPV acquisition. The increased risk of HPV persistence observed among current COC users suggests a possible influence of female sex hormones on host response to HPV infection.

The association of hormonal contraceptive use and HPV prevalence.

Women diagnosed with cervical cancer report longer duration and more recent use of combined oral contraceptives (COCs). It is unclear whether COC use is associated with upstream events of human papillomavirus (HPV) infection prior to development of clinical disease. The objective of our study was to assess the association of contraceptive use on the risk for prevalent HPV infection in a cohort of long-term hormonal contraceptive (HC) users. One thousand and seventy (n = 1,070) HIV-negative women aged 20-37 from Thailand enrolled in a prospective study of the natural history of HPV. Baseline HPV genotype information, recency and duration of HC use, sexual behavior, other sexually transmitted infection (STI) information and cervical cytology and histology were assessed. At enrollment, 19.8% and 11.5% of women were infected with any HPV or any high-risk (HR)-HPV, respectively. After adjustment for age, current and past sexual risk behaviors, STI history and cytology, the use of COCs for >6 years was found to be associated with an increased risk of infection with any HPV [prevalence ratio (PR): 1.88 (1.21, 2.90)] and any HR-HPV [PR: 2.68 (1.47, 4.88)] as compared to never users. Recent, long-term COC use was associated with an increased risk for prevalent HPV infection independent of sexual behavior and cervical abnormalities. No similar association was observed for recent or long duration use of progestin-only contraceptives (i.e., depomedroxyprogesterone acetate). These data suggest that COC use may impact early upstream events in the natural history of HPV infection.

Screening of cervical neoplasia by using pap smear with speculoscopy compared with pap smear alone.

OBJECTIVE: The objective was to compare the sensitivity and specificity of Pap smear plus speculoscopy with Pap smear alone. MATERIAL AND METHOD: The study was conducted in the Gynecology Clinic, Rajavithi hospital, Thailand between February 1st and July 31st 2003. Women who made a request for cervical screening underwent a Pap smear, speculoscopy and colposcopy. Colposcopically directed biopsies were obtained from women who had a positive colposcopy. Analytical methods were applied. RESULTS: Of 257 women recruited to the study, Pap smear plus speculoscopy could increase sensitivity from 6.67% with Pap smear alone and to 33.33% when Pap smear plus speculoscopy is used. The false negative rate was reduced from 93.33% with Pap alone and to 66.67% with Pap smear plus speculoscopy. In using Pap smear alone compared with combination of two tests, the specificity decreased from 97.52% to 77.68% and false positive rate increased from 2.48% to 22.31%, respectively. CONCLUSION: Adding speculoscopy to the Pap smear is able to significantly increase the sensitivity of the cervical screening. It also reduces the 'false negative" result. However, as expected, the specificity slightly decreases, due to the false positive from speculoscopy itself. One solution is to defer colposcopy for 6 months and to perform colposcopy only if either Pap smear or speculoscopy is positive.