Aim: Ovarian cancer is one of the most common gynecologic cancers that has the highest mortality rate. Considering the fact that knowledge on the incidence, mortality of ovarian cancer, as well as its risk factors is necessary for planning and preventing complications, this study was conducted with the aim of examining the epidemiology and risk factors of ovarian cancer in the world. Materials and methods: In order to access the articles, Medline, Web of Science Core Collection, and Scopus databases were searched from their start to the year 2018. Full-text, English observational studies that referred to various aspects of ovarian cancer were included in the study. Results: In total, 125 articles that had been published during the years 1925–2018 were entered into the study. Ovarian cancer is the seventh most common cancer among women. Increased risk factors of cancer have led to an upward trend in the incidence of cancer around the world. In 2018, 4.4% of entire cancer-related mortality among women was attributed to ovarian cancer. Although the incidence of cancer is higher among high Human Development Index (HDI) countries, the trend of mortality rate tends to be reversing. Various factors affect the occurrence of ovarian cancer, from which genetic factor are among the most important ones. Pregnancy, lactation, and oral contraceptive pills play a role in reducing the risk of this disease. Conclusion: This study provides significant evidence about ovarian cancer. Considering the heavy burden of ovarian cancer on women's health, preventive measures as well as health education and early detection in high risk groups of women are highly recommended. Although some risk factors cannot be changed, a focus on preventable risk factors may reduce the risk of ovarian cancer. More studies are needed to explore the role of unclear risk factors in ovarian cancer occurrence.

Background Pregnancy is one of the most sensitive and important stages of women's life. Maternal health literacy is the key to achieving a healthy pregnancy. It also affects pregnancy outcomes by improving the quality of health care in this period. The aim of this study was to develop and evaluate the psychometric properties of maternal health literacy inventory in pregnancy (MHELIP). Methods This sequential, exploratory and mixed study was carried out in two parts (qualitative study and psychometric evaluation of the tool) in Tehran in 2016-18. The first part involved a qualitative content analysis with a traditional approach using in-depth, semi-structured and personal interviews with 19 eligible pregnant women. Then, the pool of items extracted from the qualitative part was completed by reviewing the existing literature and tools. In the second part, the overlapping items were summarized and the tool was validated. In order to evaluate the construct validity, a cross-sectional study was conducted with the participation of 320 pregnant women. Data analysis was performed by SPSS-19 software using exploratory factor analysis and reliability tests (Cronbach's alpha and ICC). Results Findings of qualitative part produced a pool of 120 items that reached to 124 items after reviewing the literature. After confirming face and content validity by calculating CVI and CVR for each item, 53 items remained in the pool. Finally, the results of exploratory factor analysis confirmed a tool with 48 items in four factors, explaining 46.49% of the variance of total variables of the tool. Reliability of the tool was approved by Cronbach's alpha = 0.94