title: A cross sectional study on fertility knowledge in Japan, measured with the Japanese version of Cardiff Fertility Knowledge Scale (CFKS-J).
abstract: BACKGROUND
  A recent survey of 79 countries showed that fertility knowledge was lower in Japan than in any other developed country. Given the fertility decline in Japan and the importance of fertility knowledge, we conducted an online survey to examine fertility knowledge and the related factors for effective public education.
  
  
  METHODS
  We studied people aged 18-59 years old, n = 4,328 (the "General" group), and also people who had been trying to conceive for at least six months, 18-50 years old, n = 618 (the "Triers" group). Fertility knowledge was assessed using the Japanese version of the 13-item Cardiff Fertility Knowledge Scale (CFKS-J). All participants provided socio-demographic and fertility information. Participants also completed a 14-item health literacy scale and an 11-item health numeracy scale. We asked participants who were aware of age-related decline in fertility when and where they first acquired that knowledge.
  
  
  RESULTS
  The average percentages of CFKS-J items answered correctly were 53.1% in the Triers group and 44.4% in the General group (p < 0.001). Multivariate linear regression models showed in the Triers group greater fertility knowledge was associated with greater health literacy and prior medical consultation regarding their fertility. In the General group greater fertility knowledge was associated with being female, younger, university educated, currently trying to conceive, non-smoking, having higher household income, having higher health literacy and having higher health numeracy. Of those who were aware of the age-related decline in fertility, around 3% first learned the fact "at school", and around 65% first learned it "through mass media" or "via the Internet". More than 30% of the respondents first learned it "less than 5 years before" the survey.
  
  
  CONCLUSIONS
  Although fertility knowledge had improved since a previous study, possibly due to recent media coverage of age-related infertility, it was still low. Educational interventions, both in schools and in the community, may be needed to increase fertility knowledge in the general population because most people obtain fertility knowledge from mass media, which has been shown to often present distorted and inaccurate fertility information.
authors: Graduate School of Medicine, The University of Tokyo, 7-3-1, Hongo, 113-0033, Bunkyo-ku, Tokyo, Japan. kuwayama-tky@umin.ac.jp.|Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan. kuwayama-tky@umin.ac.jp.
authors: Eri
authors: E
authors: Maeda
authors: Department of Preventive Medicine, Graduate School of Sports and Health Sciences, Daito Bunka University, 560, Iwadono, 355-8501, Higashimatsuyama-shi, Saitama, Japan. hsugimor@ic.daito.ac.jp.
authors: Hiroki
authors: H
authors: Sugimori
authors: Graduate School of Medicine, The University of Tokyo, 7-3-1, Hongo, 113-0033, Bunkyo-ku, Tokyo, Japan. f-naka@m.u-tokyo.ac.jp.
authors: Fumiaki
authors: F
authors: Nakamura
authors: Graduate School of Medicine, The University of Tokyo, 7-3-1, Hongo, 113-0033, Bunkyo-ku, Tokyo, Japan. yasukik@m.u-tokyo.ac.jp.
authors: Yasuki
authors: Y
authors: Kobayashi
authors: Graduate School of Medicine, The University of Tokyo, 7-3-1, Hongo, 113-0033, Bunkyo-ku, Tokyo, Japan. jgreen@m.u-tokyo.ac.jp.
authors: Joseph
authors: J
authors: Green
authors: Department of Public Health and Environmental Medicine, The Jikei University School of Medicine, 3-25-8, Nishishinba-shi, 105-8461, Minato-ku, Tokyo, Japan. suka@jikei.ac.jp.
authors: Machi
authors: M
authors: Suka
authors: Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 7-3-1, Hongo, 113-0033, Bunkyo-ku, Tokyo, Japan. a-okmoto@mail.ecc.u-tokyo.ac.jp.
authors: Masako
authors: M
authors: Okamoto
authors: Cardiff Fertility Studies Research Group, School of Psychology, Cardiff University, Tower Building, Park Place, CF10 3AT, Cardiff, South Wales, UK. Boivin@cardiff.ac.uk.
authors: Jacky
authors: J
authors: Boivin
authors: Center of Maternal-Fetal, Neonatal and Reproductive Medicine, National Center for Child Health and Development, 2-10-1, Okura, 157-0074, Setagaya-ku Tokyo, Japan. saitou-hi@ncchd.go.jp.
authors: Hidekazu
authors: H
authors: Saito
mesh_terms: D000293:Adolescent; D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D005298:Fertility; D006266:Health Education; D007722:Health Knowledge, Attitudes, Practice; D057220:Health Literacy; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D011594:Psychometrics; D015203:Reproducibility of Results; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D055815:Young Adult
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