Effects of fertility education on knowledge, desires and anxiety among the reproductive-aged population: findings from a randomized controlled trial

STUDY QUESTION: What are the effects of fertility education on knowledge, childbearing desires and anxiety? SUMMARY ANSWER: Providing fertility information contributed to greater knowledge, but increased anxiety. WHAT IS KNOWN ALREADY: Past studies have found that exposure to educational material improved fertility awareness and changed desires toward childbearing and its timing. Existing educational websites with evidence-based medical information provided in a non-judgmental manner have received favorable responses from reproductive-aged men and women. STUDY DESIGN, SIZE, DURATION: This three-armed (one intervention and two control groups), randomized controlled trial was conducted using online social research panels (SRPs) in Japan in January 2015. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 1455 participants (726 men and 729 women) between 20 and 39 years of age who hoped to have (more) children in the future were block-randomized and exposed to one of three information brochures: fertility education (intervention group), intake of folic acid during pregnancy (control group 1) or governmental financial support for pregnancy and childbirth (control group 2). Fertility knowledge was measured with the Japanese version of the Cardiff Fertility Knowledge Scale (CFKS-J). Knowledge, child-number and child-timing desires, subjective anxiety (i.e. whether participants felt anxiety [primary outcome]), and scores on the State-Trait Anxiety Inventory were assessed immediately after exposure. Non-inferiority comparisons were performed on subjective anxiety with non-inferiority declared if the upper limit of the two-sided 95% confidence interval (CI) for risk difference did not exceed a margin of 0.15. This test for non-inferiority was only performed for subjective anxiety; all the other variables were tests of superiority. MAIN RESULTS AND THE ROLE OF CHANCE: Posttest scores on the CFKS-J (mean, SD) were higher in the intervention group than that of the control groups: intervention versus Control 1 and versus Control 2: 52.8 (28.8) versus 40.9 (26.2) (P< 0.001) versus 45.1 (27.1) (P = 0.003) among men and 64.6 (26.0) versus 50.8 (26.9) (P< 0.001) versus 53.0 (26.4) (P< 0.001) among women. The percentage of participants who felt subjective anxiety after exposure to the intervention brochure was significantly higher than that of the control groups: intervention versus Control 1 and versus Control 2: 32.6 versus 17.8% (risk difference [RD] = 0.149, 95% CI: 0.073–0.225) versus 14.5% (RD = 0.182, 95% CI: 0.108–0.256) among men, and 50.2 versus 26.3% (RD = 0.239, 95% CI: 0.155–0.322) versus 14.0% (RD = 0.362, 95% CI: 0.286–0.439) among women. Non-inferiority of the intervention was inconclusive (i.e. the CI included 0.15) among men whereas inferiority was declared among women. The incidence of anxiety was higher in the intervention group than that of the control groups especially among men aged 30 and older and among women aged 25 and older. No difference existed in childbearing desires between groups after exposure. LIMITATIONS, REASONS FOR CAUTION: The possibility of selection bias associated with the use of SRPs (higher socioeconomic status and education) and volunteer bias toward those more interested in fertility may limit the generalizability of these findings. WIDER IMPLICATIONS OF THE FINDINGS: In addition to education targeting a younger generation, psychological approaches are needed to alleviate possible anxiety caused by fertility information. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by National Center for Child Health and Development, Seiiku Medical Study Grant (24-6), the Daiwa Foundation Small Grants and Grant-in-Aid for JSPS Fellows (26-1591). No competing interest declared. TRIAL REGISTRATION NUMBER: UMIN Clinical Trials Registry. Trial registration number, 000016168. TRIAL REGISTRATION DATE: 13 January 2015. DATE OF FIRST PATIENT'S ENROLMENT: 15 January 2015.