Prevalence, incidence and clearance of human papillomavirus infection among young primiparous pregnant women in Kampala, Uganda

Abstract

The proportion of women who have already been exposed to human papillomavirus (HPV) infection by the time they first become pregnant, and the influence of pregnancy and delivery on the course of HPV infection are unclear. In Kampala, Uganda, 987 young primiparous pregnant women aged <25 years had gynaecological examination and liquid-based cytology. In the follow-up, women acted as their own controls, i.e., 1st/2nd versus 3rd trimesters (105 women), and during pregnancy versus after delivery (289 women). HPV was assessed using highly sensitive PCR assays. Prevalence of HPV and HIV infections at baseline were 60.0% and 7.3%, respectively. HPV16 and 18 were detected in 8.4% and 5.8%, respectively, i.e., less frequently than HPV51 (8.7%) and 52 (12.1%). At follow-up new HPV infections were detected in 42.9% of women between the 1st/2nd and 3rd trimesters, and 38.1% between pregnancy and delivery, but 50.4% and 71.8% of HPV infections, respectively, cleared, leaving HPV prevalence unchanged in the different periods. Prevalence of cytological abnormalities diminished after delivery (from 21.2% to 12.4%). Presence of genital warts and sexually transmitted infections other than HPV were the strongest risk factors for prevalent or incident HPV infection. Clearance was lower among HIV-positive women. In conclusion, HPV prevalence was high in primiparous women in Uganda, but pregnancy did not seem to be a period of special vulnerability to the infection. ' 2008 Wiley-Liss, Inc.Key words: human papillomavirus; HIV; Uganda; pregnant adolescents; epidemiology Prophylactic vaccines against human papillomavirus (HPV) 16 and 18 are recommended for girls who are not yet sexually active.1 In low-resource countries where the burden of cervical cancer is high, however, a catching up of less young women when they have contacts with medical facilities (e.g., at first delivery) may be worth considering if the number of young women not yet infected by HPV vaccine types is low. Furthermore, although high parity and young age at first birth are risk factors for cervical cancer, even after adjustment for sexual behavior, 2 relatively few studies have provided information on the influence of pregnancy status on the incidence and clearance of HPV infection. Depending upon the study, HPV detection in pregnant women was shown to be higher than, 3,4 or similar to 5-8 HPV infection among nonpregnant women.To further elucidate this issue, we evaluated prevalence, incidence and clearance of HPV infection between the 1st/2nd and 3rd trimesters of pregnancy, and between pregnancy and after delivery, among young primiparous pregnant women in Kampala, Uganda. Material and methods Study population and follow-upPrimiparous pregnant women aged below 25 years residing within a 20 km radius for the previous 6 months and presenting themselves for antenatal services at the Naguru Health Centre, located in a suburb of Kampala, Uganda, between May and November 2004, were invited to join the study. Refusals to participate were few (approximately 2%).Trained m...

Epidemiology of human papillomavirus genotypes in pregnant Japanese women

“…Several reports show that the prevalence of HPV infection in pregnant women is variable at 10-60%, depending on age, region and HPV detection methods. [11][12][13][14] The HPV infection rate in pregnant women in this report was 35%. There are few reports of HPV infection rates in pregnant Japanese women.…”

Differences in incidence and co‐occurrence of vaccine and nonvaccine human papillomavirus types in Finnish population before human papillomavirus mass vaccination suggest competitive advantage for HPV33

“…[3][4][5] Due to high transmission probability and tendency to persist concomitant infections by high-risk (hr) HPVs are common. [5][6][7][8][9][10] Furthermore, multiple infections are associated with an even higher increased risk of developing cervical neoplasia. 10 Two highly efficacious HPV vaccines have now been licensed world wide.…”

Prevalência de infecção por HPV em jovens primíparas e fatores associados

“…A grande variação -de 5% a 59% -na prevalência da infecção genital por HPV no período gestacional observada em estudos anteriores (ChangClaude et al, 1996;Tenti P et al, 1999;Eppel et al, 2000;Chan PK et al, 2002;Smith EM et al, 2004;Takakuwa et al, 2006;Banura et al, 2008b) pode ser explicada por alguns fatores como: avaliação de gestantes oriundas de populações com grandes diferenças na prevalência dessa infecção, pela menor sensibilidade dos testes empregados para a detecção do DNA-HPV nos estudos iniciais, pela utilização de diferentes tipos de amostras para a detecção do DNA viral -coletadas em diversas fases do período gestacional -e, ainda, pela inclusão de gestantes pertencentes a grupos etários distintos.…”

“…Alguns autores relataram que a gravidez pode ser um fator de risco para essa infecção, que tende, porém, a reverter após o parto de forma semelhante à que ocorre com as lesões cervicais -as quais podem apresentar regressão espontânea como conseqüência da intensa reação inflamatória sofrida pelo colo uterino após o parto, que estimularia uma resposta imunológica local (Ahdoot et al, 1998;Banura et al, 2008b;Hunter et al, 2008 Recentemente, prevalência muito semelhante à encontrada no presente estudo foi relatada em uma coorte que incluiu 987 primigestas com idade inferior a 25 anos, em Kampala−Uganda (Banura et al, 2008b). Nesse estudo africano foram realizadas três medidas da prevalência da infecção por HPV, que permaneceu ao redor de 60% tanto nos diferentes trimestres da gestação como no período após o parto (Banura et al, 2008b).…”

“…Também não se obteve diferença estatisticamente significante na prevalência da infecção por HPV em gestantes e em não gestantes, pareadas por idade, em Hong Kong-China, país com baixa incidência de câncer cervical, onde se observou baixa prevalência, respectivamente 10% e 11%, nesses dois grupos (Chan et al, 2002). A grande variação na prevalência da infecção pelo HPV observada em gestantes, com valores oscilando de 5% a 59% (Chang-Claude et al, 1996;Tenti P et al, 1999;Eppel et al, 2000;Chan et al, 2002;Smith et al, 2004;Takakuwa et al, 2006;Banura et al, 2008b) pode ser explicada por inúmeras diferenças nos desenhos utilizados nos diferentes estudos. Nestes, foram empregadas múltiplas técnicas de biologia molecular com variação na sensibilidade para a detecção do DNA viral, além da avaliação de gestantes pertencentes a populações com grandes diferenças na prevalência dessa infecção (Arena et al, 2002).…”