Human papillomavirus infection and spontaneous abortion: a case-control study performed in Mexico.

OBJECTIVE: To investigate if HPV cervical infection is associated with spontaneous abortion in a Mexican population. STUDY DESIGN: Case control study including 281 women from two Social Security Hospitals in Merida, Mexico. Cases were women with spontaneous abortion attending for curettage, and controls were pregnant women at term who attended for delivery. HPV molecular detection and typing of HPV 16, 18, 58 and 6/11 was performed on cervical samples, and TORCH serology IgM tests (against T. gondii, CMV, HSV) were performed on cases. Data were analyzed using Chi square, odds ratio and linear regression tests. RESULTS: HPV global prevalence was 19.8% (24.4% in cases and 15.2% in controls). HPV types 16 and 58 were the most frequently detected in both groups. Multiple HPV types concurrent infection were found in 31.4% of typified samples. Amongst cases 27.3% of HPV positive women reported at least one previous pregnancy loss; compared to 17.43% amongst HPV negative women. Nevertheless, HPV was not significantly associated with spontaneous or to repetitive abortion. Cases were 60.2% positive to any TORCH agent, although it was not significantly associated to referred miscarriage history. Spontaneous abortion was associated to a previous pregnancy loss and to women's age older than 35 years old. HPV infection was significantly associated to alcohol intake before pregnancy and to multiple sexual partners. CONCLUSION: HPV cervical infection was not associated with spontaneous abortion. HPV in spontaneous abortion and other adverse pregnancy outcomes merits further study.

Advances in cervical cancer control and future perspectives.

The knowledge that the persistent infection with high-risk (HR) human papillomavirus (HPV) is the etiological factor in the development of cervical cancer has led to the development of the HPV DNA detection methods as well as the prophylactic vaccine against the most common HR-HPV types, HPV 16 and 18. Despite HPV vaccination, cervical cancer screening will remain the main preventive measure for both vaccinated and non-vaccinated women, but the nature of screening and management of women with cervical disease is being adapted to the new technologies. Although, HPV DNA detection is more sensitive that cytology, its specificity is lower, since most HPV infections are transient. Therefore, other methods are considered to improve the management of women with cervical disease. Typing of HPV DNA and viral load measurements are still used for research purposes only. Detection of viral oncogene E6/E7 transcripts, which is the marker of the productive infection, is a promising tool for follow-up of HPV DNA-positive women. The detection of p16INK4a over-expression, as an indirect test of E6/E7 expression, is used for confirmation of cervical neoplasia. Despite the lack of standardization, the detection of p16INK4a is useful in clinical settings, however its reproducibility in the management of low-grade and borderline cases is low. Future perspectives include the determination of the methylation status of several cellular genes that could predict the progression of the disease.

The planning of cervical cancer screening programmes in eastern Europe: is viral testing a suitable alternative to smear testing?

Cervical cancer screening with human papillomavirus (HPV) DNA testing has potential advantages over conventional, smear testing in that it can predict cases in which invasive cancers are more likely to develop, may be cheaper to implement and improve compliance. In areas of the world where little formalized cervical cancer screening takes place, or where health resources are limited, HPV testing has been suggested as a possible alternative for primary screening. In this paper we demonstrate the use of mathematical modelling to evaluate the effects of setting up screening programmes in Eastern Europe with HPV DNA testing as the primary screening tool and compare it with conventional smear testing. The impact of screening is measured in terms of the life years gained and the resulting resource usage and cost. We investigate several screening options with different screening intervals and age ranges for the target population.