This study was funded by the special research fund, university of Antwerp (BOF UA). None of the authors has any conflict of interest to declare.

Six Sigma is a more efficient way to control quality, but the lack of TEa targets for many analytes and the sometimes inconsistent TEa targets from different sources are important variables for the interpretation and the application of Sigma metrics in a routine clinical laboratory. Sigma metrics are a valuable means of comparing the analytical quality of two or more analyzers to ensure the comparability of patient test results.

Persistent high-risk human papillomavirus (HPV) infection is strongly associated with the development of high-grade cervical intraepithelial neoplasia (CIN) or cancer. Not all persistent infections lead to cancer. Viral load measured at a single time-point is a poor predictor of the natural history of HPV infections. However the profile of viral load evolution over time could distinguish nonprogressive from progressive (carcinogenic) infections. A retrospective natural history study was set up using a Belgian laboratory database including more than 800,000 liquid cytology specimens. All samples were submitted to qPCR identifying E6/E7 genes of 18 HPV types. Viral load changes over time were assessed by the linear regression slope. Database search identified 261 untreated women with persistent type-specific HPV DNA detected (270 infections) in at least three of the last smears for a average period of 3.2 years. Using the coefficient of determination (R²) infections could be subdivided in a latency group (n = 143; R² < 0.85) and a regressing group (n = 127; R² ≥ 0.85). In (≥3) serial viral load measurements, serial transient infections with latency is characterized by a nonlinear limited difference in decrease or increase of type-specific viral load (R² < 0.85 and slopes between 2 measurements 0.0010 and −0.0010 HPV copies/cell per day) over a longer period of time (1553 days), whereas regression of a clonal cell population is characterized by a linear (R² ≥ 0.85) decrease (−0.0033 HPV copies/cell per day) over a shorter period of time (708 days; P < 0.001). Using serial HPV type-specific viral load measurements we could for the first time identify regressing CIN2 and CIN3 lesions. Evolution of the viral load is an objective measurable indicator of the natural history of HPV infections and could be used for future triage in HPV-based cervical screening programs.

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Background: Sexually transmitted infections are a major cause of infertility. Human papillomavirus (HPV) infection is one of the most common viral infections of the female genital tract. Only a limited number of studies have investigated the influence of HPV on fertility and its impact remains controversial. Objective: We investigated the relationship between cervical HPV infection and pregnancy outcome after intrauterine insemination (IUI). Since other sexually transmitted infections could also influence outcome, we also analyzed the influence of Trichomonas vaginalis (TV) and Chlamydia trachomatis (CT) on pregnancy outcome. Methods: We performed a retrospective analysis of 590 women who underwent 1,529 IUI cycles at AML between 2010 and 2014. Positivity of 18 different HPV types (6, 11, 16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 67, 68) and TV was assessed by PCR in cervical cytology specimens. CT status was ascertained by detection of IgA/IgG antibodies on serum samples or by PCR on cervical swabs. Results: The HPV prevalence per IUI cycle was 11.0 and 6.9% for CT; none of the women tested positive for TV. HPV-positive women were six times less likely to become pregnant after IUI (1.87 vs. 11.36%; p = 0.0041). There was no significant difference in pregnancy rates between women with or without a history of CT (8.51 vs. 11.10%; p > 0.05). Conclusion: Detection of HPV is associated with a negative IUI outcome.