A cross sectional study on fertility knowledge in Japan, measured with the Japanese version of Cardiff Fertility Knowledge Scale (CFKS-J)

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