Despite numerous available resources of evidence, the results about the frequency of pregnancy-associated cancer (PAC) still show poor comparability due to dissimilarities in the study design and methodology, inclusion criteria, incoherent duration of follow-up and a heterogeneous reference population. We conducted a systematic review of population-based studies on PAC published up to December 2019, to provide updated research on this topic, highlighting strengths and limitations. Of the 24 papers included, 11 considered all types of tumors and 13 dealt with specific types of cancer. Differences in the procedures for estimating the frequency of PAC emerged even among population studies. However, we found consistent results for overall frequency of PAC— around 1/1000 pregnancies. Our review suggests that about 25% of PAC cases are diagnosed during pregnancy, confirming the hypothesis of an excess of diagnosis in the postpregnancy period. Sparse and inconsistent results were found regarding a potential increase in the frequency of PAC over calendar years. Alignments in the strategy to identify PAC are needed to overcome methodological weaknesses.

The World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) introduced in 2007, and updated in 2018, nutrition-related recommendations for cancer prevention. Previous studies generally reported inverse associations of breast cancer with the 2007 recommendations, while no study has yet evaluated the association with the 2018 guidelines. We investigated the association between adherence to the 2018 WCRF/AICR recommendations and breast cancer risk in a case–control study from Italy and Switzerland (1991–2008) including 3034 incident histologically-confirmed breast cancer cases and 3392 hospital controls. Adherence to the 2018 guidelines was summarized through a score incorporating eight recommendations (body fatness, physical activity, consumption of wholegrains/vegetables/fruit/beans, “fast foods” and other processed foods high in fat, starches, or sugars, red/processed meat, sugar-sweetened drinks, alcohol, breastfeeding), with higher scores indicating higher adherence. Odds ratios (OR) were estimated using multiple logistic regression models. We also conducted a meta-analysis including 15 additional studies using random-effects models. In our case–control study, adherence to the 2018 WCRF/AICR guidelines was inversely associated with breast cancer, with ORs of 0.60 (95% confidence interval (CI), 0.51–0.70) for a score ≥5.5 vs. ≤4.25, and of 0.83 (95% CI, 0.79–0.88) for a 1-point increment. In our study, 25% of breast cancers were attributable to low-to-moderate guideline adherence. In the meta-analysis, the pooled relative risks (RRs) were 0.73 (95% CI, 0.65–0.82, p heterogeneity among studies < 0.001) for the highest vs. the lowest WCRF/AICR score category, and 0.91 (95% CI, 0.88–0.94, p heterogeneity < 0.001) for a 1-point increment. This work provides quantitative evidence that higher adherence to the WCRF/AICR recommendations reduces the risk of breast cancer, thus opening perspectives for prevention.

The effective use of dietary patterns (DPs) remains limited. There is a need to assess their consistency over multiple administrations of the same dietary source, different dietary sources, or across different studies. Similarly, their generalizability should be based on a previous assessment of DP construct validity. However, to date, no systematic reviews of reproducibility and validity of a posteriori DPs have been carried out. In addition, several methodological questions related to their identification are still open and prevent a fair comparison of epidemiological results on DPs and disease. A systematic review of the literature on the PubMed database was conducted. We identified 218 articles, 64 of which met the inclusion criteria. Of these, the 38 articles dealing with reproducibility and relative and construct validity of DPs were included. These articles (published in 1999-2017, 53% from 2010 onwards) were based on observational studies conducted worldwide. The 14 articles that assessed DP reproducibility across different statistical solutions examined different research questions. Included were: the number of food groups or subjects; input variable format (as well as adjustment for energy intake); algorithms and the number of DPs to retain in cluster analysis; rotation method; and score calculation in factor analysis. However, we identified at most 3 articles per research question on DP reproducibility across statistical solutions. From another 15 articles, reproducibility of DPs over shorter (≤1 y) time periods was generally good and higher than DP relative validity (as measured across different dietary sources). Confirmatory factor analysis was used in 15 of the included articles. It provided reassuring results in identifying valid dietary constructs characterizing the populations under consideration. Based on the available evidence, only suggestive conclusions can be derived on reproducibility across different statistical solutions. Nevertheless, most identified DPs showed good reproducibility, fair relative validity, and good construct validity.

Background: Since the 1970s, several studies found that sperm concentration (SC) and total sperm count (TSC) constantly worsened over time, mainly in high‐income countries.Objectives: To evaluate whether the decreasing trend in sperm count is continuing in Western European countries and USA, we performed a systematic review and meta‐regression analysis.Materials and methods: Embase and Pubmed/Medline were searched papers published in English in the 2000–2020 period limiting the search to data collected in the USA and Western European countries.Results: We identified 62 articles and pooled information on 24,196 men (range 10–2,523), collected from 1993 to 2018. Considering all the studies, random‐effects meta‐regression analyses showed no significant trend for SC (slope per year −0.07 mil/mL, p‐value = 0.86). Negative trends of SC were detected in Scandinavian countries (slope per year −1.11 mil/mL, 95% CI: −2.40 to +0.19; p‐value = 0.09), but the findings were statistically not significant. No significant trends of SC were detected in Central Europe (slope per year +0.23, 95% CI −2.51 to +2.96; p‐value = 0.87), the USA (slope per year +1.08, 95% CI −0.42 to +2.57; p‐value = 0.16), and Southern Europe (slope per year +0.19, 95% CI −0.99 to +1.37; p‐value = 0.75).We have analyzed separately findings from studies including sperm donors, fertile men, young unselected men (unselected men, study mean age < 25 years) and unselected men (unselected men, study mean age ≥ 25 years). No significant trends of SC were observed among sperm donors (slope per year −2.80, 95% CI −6.76 to +1.17; p‐value 0.16), unselected men (slope per year −0.23, 95% CI −1.58 to +1.12; p‐value 0.73), young unselected men (slope per year −0.49, 95% CI −1.76 to +0.79; p‐value 0.45), fertile men (slope per year +0.29, 95% CI −1.09 to +1.67; p‐value 0.68).Discussion and conclusion: The results of this analysis show no significant trends in SC, in USA, and selected Western European countries.

Background: Rubella, syphilis, toxoplasmosis, cytomegalovirus (CMV), hepatitis B (HBV) and C (HCV), HIV, and Group B Streptococcus (GBS) infections may have very severe outcomes during pregnancy, and for this reason, monitoring of infections in pregnant women is a requirement of prenatal assistance. Aims: To describe coverage and outcome of the screening for rubella, syphilis, toxoplasmosis, CMV, HBV, HCV, HIV, and Group B Streptococcus in pregnancy in the Autonomous Province of Trento, Northern Italy (538,600 inhabitants). Methods: We analysed the coverage and outcome of the above-mentioned screenings among women who delivered in the hospitals of the Province of Trento between 2007 and 2014 (N = 38,712). Screenings were grouped according to characteristics such as recommendation by national and local guidelines, scheduling of the tests, operating methods, and charge. We also estimated odds ratios (ORs) for missing screening for selected infections through multiple logistic regression. Results: Estimated uptake of antenatal screening was 99.7% for rubella, 99.3% for syphilis, 99.7% for toxoplasmosis, 98.1% for HIV infection, 99.0% for HBV, 98.9% for HCV, 94.0% for GBS infection, and 75.4% for CMV infection. The overall prevalence of immunity was 94.1% for rubella, 24.2% for toxoplasmosis, and 64.2% for CMV. The rate of seroconversion in pregnant women was 0.02% for rubella, 0.29% for toxoplasmosis, and 0.75% for CMV. The overall prevalence of infection was 0.94% for HBV, 0.53% for HCV, 22.3% for GBS, 0.29% for syphilis, and 0.13% for HIV. We found a significant positive association for all screening tests, between lack of testing and late first medical examination in pregnancy (ORs ranging from 1.20 to 1.66 for the first medical visit in the second trimester and ORs ranging from 1.60 to 5.88 for the first medical visit in third trimester, compared to early medical visit in the first trimester). Compared to Italian citizenship, foreign citizenship of the mother was also positively associated with absence of screening (ORs ranging from 1.30 to 1.53). A significant inverse association was observed for calendar year of delivery (ORs ranging from 0.71 to 0.97, for 1 year increment). Less educated mothers and pluriparae were also at higher risks of not being tested. Analysis of the association with mother age showed different heterogeneous effects. Conclusions: Our study indicates that the attention to screening and detecting infected cases is growing over the time. In addition, care delivered during pregnancy has a leading role in determining coverage of the examinations. Immigrant, pluriparous and less educated women need particular attention.