Abstract
Lifestyle factors greatly affect fertility, making improving the fertility awareness of men an urgent matter. This study aimed to assess changes in fertility awareness and lifestyle behaviors among men after viewing a video focusing on sperm quality. The participants in this single-group, longitudinal study were employed men in their 20s and 30s without children. They were administered an online questionnaire survey three times: before, immediately after, and 2 weeks after viewing the video. This study was conducted in January 2024 after undergoing institutional ethics review. A total of 69 participants were included in the analysis. The results indicated that the proportion of participants interested in fertility after viewing the video increased significantly, from 44.9% (n = 31) to 76.8% (n = 53; p < .001). Of the 13 lifestyle behaviors covered in the survey, a significant difference was seen for only one after 2 weeks: walking for approximately 5 min after sitting for approximately 1 hr (p = .035). The percentage of participants whose awareness of improvements in their lifestyle behavior had changed 2 weeks after viewing the video ranged from 19.1% to 39.1% lower for all 13 items. The change in awareness of each lifestyle behavior was analyzed based on participants who had already regularly engaged in the behavior and participants who had not, and significant differences were seen for seven behaviors. These results indicate that the video was effective for stimulating men’s interest in their own fertility. However, challenges remain in changing lifestyle behaviors.
Introduction
Total sperm count, an index of male fertility, is decreasing on a global scale, and this trend has accelerated in the twenty-first century (Levine et al., 2023). According to the World Health Organization (2023), approximately 17.5% of the adult population, or one in every six people, has experienced infertility, with no variability in lifetime prevalence seen among high-, low-, and middle-income countries. Infertility is thus becoming a major global health issue (World Health Organization, 2023). A survey conducted in Japan in 2021 found that one in every 4.4 couples had undergone infertility testing and treatment, and that infertility is on the rise in Japan (National Institute of Population and Security Research, 2023). In the future, as adult men and women postpone marriage, childbirth will be delayed, and the number of couples hoping to have children at an age when fertility declines will continue to increase.
In addition to aging, lifestyle factors, including obesity, electromagnetic radiation exposure (mobile phone/laptop computer use), diet/nutrition, recreational drug, tobacco, and alcohol use, psychological stress, radiation exposure, strenuous exercise, and long bicycle rides, play a major role in male sperm quality (Durairajanayagam, 2018; Ilacqua et al., 2018; Rotimi & Singh, 2024). A study conducted in Japan showed that impaired spermatogenesis accounted for 82.4% of male infertility, and that 42.1% of the total was idiopathic (Yumura et al., 2017). Lifestyle is thought to play a role in such medically unexplained spermatogenic impairment (Komiya et al., 2020). A lifestyle factor that can cause impaired spermatogenesis is scrotal heat stress, which is a substantive risk factor for male infertility. A testicular temperature lower than body temperature is more suitable for sperm production, and the scrotum acts to lower testicular temperature by 2–4 °C. Scrotal heat stress gives rise to reactive oxygen species, damages sperm DNA, and causes sperm DNA fragmentation and apoptosis, thereby reducing fertilizability (Durairajanayagam, 2018; Takeshima et al., 2020). In a study conducted in Japan in which 564 men (mean age, 35.5 years) underwent fertility screening before or shortly after getting married, 25.4% did not meet the World Health Organization criteria for at least one of the following three items: semen volume, sperm concentration, and sperm motility rate (Tsujimura et al., 2020). Therefore, lifestyle-focused education is urgently needed to stem the decrease in male fertility.
During infertility treatment or after receiving poor semen test results, advice regarding dietary management and modifications to physical activity levels to is given to improve semen quality; however, men who do not visit medical institutions do not receive this advice. A systematic review of the literature conducted in 2024 found that only two intervention studies had been conducted on men in the general population (Krishnan et al., 2024). In one study, risk factor-related fertility awareness in 49 adult males (aged 18–45 years) increased after a 2-week intervention using a mobile health app (Kruglova et al., 2021). The other study, a randomized controlled trial involving 201 men (age range, 18–50 years), found that counseling based on a reproductive life plan had a positive effect on fertility awareness (Bodin et al., 2018). Those studies indicated that education regarding the lifestyle factors that affect fertility is effective in increasing fertility awareness (Bodin et al., 2018; Kruglova et al., 2021).
Adult Japanese men and women do not receive fertility education in school, and as a result, their knowledge of fertility is the lowest among developed countries (Bunting et al., 2013). In particular, men are not interested in fertility until they are close to marriage or childbirth age (Nakada-Nakagomi et al., 2025). Given this background, we considered that the first step in improving fertility awareness could be to foster men’s interest in their own fertility. Therefore, the present study aimed to assess changes in fertility awareness and lifestyle behaviors among men after viewing a video focusing on sperm quality and lifestyle risk factors.
Study Significance
We considered that increasing men’s own knowledge of their reproductive capacity and modifiable risk factors could enhance their fertility awareness, lead to improvements in sperm quality, positively impact their overall health and well-being, help prevent comorbidities of pregnancy and parturition, and provide health benefits for future generations. Although the worsening of semen parameters that occurs with aging cannot be halted, keeping the sperm in good condition by improving lifestyle behaviors may help improve natural pregnancy and infertility treatment outcomes.
Method
The research questions in this study were as follows: “Does viewing an educational video focused on enhancing sperm quality make reproductive-age men more interested in their own fertility?”; “Are some changes in lifestyle behaviors risk factors that affect sperm quality?”; and “Are there some changes in awareness regarding lifestyle behaviors that affect sperm quality?”
Definitions of Terms
The International Glossary on Infertility and Fertility Care defines fertility awareness as follows: the understanding of reproduction, fecundity, fecundability, and related individual risk factors (e.g., advanced age, sexual health factors such as sexually transmitted infections, and lifestyle factors such as smoking and obesity) and non-individual risk factors (e.g., environmental and workplace factors), including the awareness of societal and cultural factors affecting options to meet reproductive family planning, as well as family building needs (Zegers-Hochschild et al., 2017). For the present study, fertility awareness was defined as follows: being concerned about one’s fertility by knowing the risk factors that affect one’s own sperm quality, and being aware of better health and lifestyle behaviors.
Design and Procedure
This longitudinal study involved a pretest and two posttests following video viewing administered to one group. The study protocol is shown in Figure 1. The first questionnaire was administered online before the participants viewed the video. The second was administered immediately after the participants viewed the video. The third was administered 2 weeks after the participants viewed the video. The follow-up survey was administered 2 weeks after the participants viewed the video to have them answer the questionnaire from recall. The reason for conducting the follow-up survey 2 weeks later was to reduce the number of dropouts, as the participants would not be able to recall the content of the video or be able to respond if there was a substantial gap in time. The primary purpose of the video was to increase interest in fertility, and the content was kept to a minimum, so no behavioral changes were expected, and long-term follow-up was not conducted. Participant recruitment and study implementation were subcontracted to an internet survey company (Cross Marketing Inc., Tokyo, Japan), which conducted the online surveys. The study duration was 1 month (conducted in January 2024).
Study Protocol.
Participants and Setting
The inclusion criteria were as follows: males in their 20s to 30s (as of January 1, 2024), employed, and without children. There was no requirement regarding whether the participants had a partner, but if they did, their partner had to be non-pregnant. In addition, the participants had to be capable of understanding Japanese. There were no exclusion criteria. The reasons for selecting these participants were as follows. In a survey conducted in Japan in 2020, the mean age of first marriage for men was 31.0 years (mode, 27 years), indicating that men think most about marriage and having children in their 20s and 30s. The participants were limited to employed men because of the financial stability associated with having an income, making it likely that marriage and childbearing would be considered practical.
There was no restriction on whether the employees were regular or nonregular, and no limits were placed on annual income. Men who did not have children and whose partners were not pregnant were selected so that the participants were not certain that their fertility was sufficient to impregnate a woman. Because the video and questions were in Japanese, the participants had to be able to understand Japanese, but there were no restrictions based on nationality.
Description of the Fertility Awareness Video
An educational video about fertility that focused on sperm quality and lifestyle risk factors was developed. The duration of the video was 9 min and 9 s. The content of the video was as follows. The introduction showed that semen parameters in men are currently worsening, and that the parameters are a barometer of one’s future health. The next part described behaviors that are risk factors affecting sperm quality, as well as behaviors for coping with these risks. Items specifically mentioned included testicular thermal stimulation, prolonged sitting behavior, points to keep in mind when riding road bikes, recommendations for moderate exercise, and wearing underwear with good breathability. In addition, the practice of ejaculatory abstinence to maintain the condition of the sperm was explained. Finally, information was provided on diet and nutrition and sleep quality and quantity, which are basic and important aspects of lifestyle, as well as the need to consume zinc. Even if it is understood to be necessary, consuming a balanced diet is difficult under the constraints of daily life. Consequently, the video suggested compensating for nutritional deficiencies by eating nutritious snacks between meals (The Japan Dietetic Association, 2023). In view of the fact that some people do not wish to have children, it mentioned the need for lifestyle modifications for one’s future health. The video was created based on evidence presented in previous reports and developed in consultation with a urologist who specializes in male infertility and a university professor who specializes in sports nutrition.
Variables
The primary outcome was the percentage of participants who were interested in their own fertility after viewing the video. The questionnaire explained that “fertility is the ability to conceive a child or to impregnate a woman.” There were two secondary outcomes. The first was the change in lifestyle behaviors at 2 weeks after viewing the video, and the second was the change in awareness regarding lifestyle behaviors that are risk factors for fertility at 2 weeks after viewing the video.
The questionnaire items in the first survey were as follows. The survey conducted before the participants viewed the video asked about their attributes, interest in their own fertility, and engagement in lifestyle behaviors that affect fertility. There were eight items concerning the participants’ attributes: age, marital status, whether the participant had a partner, the participant’s wishes regarding having children in the future, previous infertility treatment, hours per day spent sitting at work, body mass index (BMI), and whether the participant regularly rode a road bike. There were a total of 13 items regarding lifestyle behaviors: three on diet and nutritional balance, two on moderate exercise, four on sitting behavior and testicular thermal stimulation, one on ejaculatory abstinence periods, and three on sleep quantity and quality. The second survey was administered after the participants viewed the video. Variables included one item regarding the change in interest in fertility and the participant’s motivation for improvement in 13 lifestyle behaviors. In addition, five items were used for an evaluation of the video—understandability, whether the content was interesting, how well it met the participant’s expectations, its usefulness, and whether the participant would recommend it to a friend—each of which was rated on a four-point Likert-type scale. There were a total of 19 items. The third survey, which was conducted 2 weeks later, included a total of 26 items on the participant’s engagement in lifestyle behaviors (13 items) and the change in the participant’s desire for lifestyle behavior improvement (13 items). In addition, participants who were already practicing each of the lifestyle behaviors were asked to indicate whether they desired further improvement in those behaviors.
The rationale for the sample size selected was as follows. The required sample size was determined to be 85 participants based on the assumption that the percentage of participants interested in their own fertility would increase from 50% before viewing the video to 70% after, and that 5% of those who were initially interested would lose interest after viewing the video. In calculating the required sample size, a significance level of 5% and a power of 80% were used. Assuming a 20% dropout rate, a sample size of 100 participants was selected. To avoid participant age bias, the subcontractor was asked to ensure that there were approximately 25 participants from each of the following age groups: 20–24 years, 25–29 years, 30–34 years, and 35–39 years.
The rationale for assuming that 50% of the participants would be interested in fertility before viewing the video was that, in a previous study, 50% of men indicated that they wanted information about physical preparation for men and women before their partner became pregnant, and 54.4% said they wanted information about the risk factors that affect fertility (Nakada-Nakagomi & Atogami, 2022).
Data Analysis
Descriptive statistics were calculated first, and then the following tests were performed. McNemar’s test was performed to examine the change in interest in fertility from before to after viewing the video and in the proportion of participants who engaged in a lifestyle behavior before and 2 weeks after viewing the video. It was thought that being motivated could lead to a change in awareness, so the percentage of participants who indicated that they were motivated to improve their lifestyle behavior immediately after viewing the video was compared with that of participants with an awareness of lifestyle behavior improvement at 2 weeks after viewing the video. Fisher’s exact test was performed to analyze the change in awareness of lifestyle behaviors at 2 weeks after viewing the video with the participants divided into those who had normally engaged in the behaviors and those who had not. All statistical analyses were conducted using IBM SPSS Statistics (version 26, IBM Corp., Armonk, NY, USA). with a two-sided 5% level of significance.
Ethical Considerations
This study was approved by the Research Ethics Committee of the International University of Health and Welfare School of Health Sciences (No. 23-Ig-210). All participants provided informed consent online before participating in the study.
Results
Program Participation and Questionnaire Collection Rate
In the first survey, 158 responses were collected, with 131 remaining after the straight-line cut. The second survey was distributed to 131 participants; 99 responses were collected, with 69 remaining after the straight-line cut. Because the survey was conducted online, the participants could not proceed to the next questionnaire item without providing a response to the current item. Consequently, there were no missing values. To ensure the validity of the responses, the 69 remaining after the straight-line cut were included in the analysis.
Demographic Characteristics
The demographic characteristics of the 69 participants are shown in Table 1. The ages of the participants were distributed roughly equally across 5-year categories. Unmarried individuals accounted for 64 participants (92.8%) and individuals with partners for 12 (17.4%). Among the 69 participants, 28 (40.6%) wanted children in the future, 12 (17.4%) did not, and 29 (42.0%) were undecided. None of the participants had undergone infertility treatment. With regard to BMI, 36 participants (52.2%) were of average body type, and 16 (23.1%) had obesity. Only five participants (7.2%) reported riding a road bike regularly. The median time spent sitting at work was 8 hr (range, 0–16 hr).
Participants’ Characteristics (N = 69).
Outcome
The changes in the number of participants interested in fertility (the primary outcome) are shown in Table 2. Before viewing the video, 31 participants (44.9%) were interested in fertility. After viewing the video, 53 participants (76.8%) were interested. Thus, the percentage interested in their own fertility after viewing the video increased significantly, χ2(1) = 14.235, p < .001. The change in the percentage of participants who engaged in each of the 13 types of lifestyle behaviors at 2 weeks after viewing the video (the first secondary outcome) is shown in Table 3. Of the 13 behaviors, a significant difference was seen only in walking for approximately 5 min after sitting for approximately 1 hr. Sixteen participants (23.2%) said they did this before viewing the video, and 25 (36.2%) said they did it 2 weeks after viewing the video, χ2(1) = 4.267, p = .035.
Level of Interest in Own Fertility and Change in Interest Level after Viewing the Educational Video.
Comparison of Engagement in Lifestyle Behaviors Before and 2 Weeks After Viewing the Video (N = 69).
The second secondary outcome was the change in awareness of lifestyle behaviors at 2 weeks after viewing the video. The percentage of participants who were motivated to improve their lifestyle behaviors immediately after viewing the video and the percentage with a change in awareness at 2 weeks after viewing the video are shown in Table 4. The percentages of participants whose awareness of improvement in lifestyle behaviors had changed at 2 weeks after viewing the video were 19.1%–39.1% lower in all items compared with the participants who were motivated to improve immediately after viewing the video. The biggest decreases were seen for items related to sleep quantity and quality, particularly refraining from smartphone use or game-playing before bedtime, which decreased by 39.1%.
Change of Awareness Regarding Lifestyle Behavior Improvement (N = 69).
Next, the change in awareness of each lifestyle behavior was analyzed according to the participants who had already regularly engaged in the behavior and the participants who had not. The results are shown in Table 5. Significant differences were seen for seven of the 13 behaviors, including walking 10,000 steps a day (p < .00001, Fisher’s exact test), being exposed to outdoor sunlight after getting up in the morning (p < .001, Fisher’s exact test), eating breakfast (p = .00, Fisher’s exact test), and walking for approximately 5 min after sitting for approximately 1 hr (p = .002, Fisher’s exact test). Thus, awareness among the participants who engaged in these seven behaviors regularly increased further as a result of viewing the video.
Changes in Awareness Regarding Lifestyle Behaviors: Regular vs. No. (N = 69).
The results of the evaluation of the educational video, which was based on a four-point scale, are shown in Table 6. The total percentage for the two highest ratings was > 80% for understandability (n = 60, 86.9%) and interesting content (n = 59, 85.5%). The total was 75.4% (n = 52) for how well the video met the participant’s expectations, 75.3% (n = 52) for its usefulness to the participant, and 60.8% (n = 42) for whether the participant would recommend it to a friend.
Evaluation of Educational Video (N = 69).
Discussion
Changes in Men’s Interest in Their Own Fertility and Lifestyle Behaviors
In this study, viewing a video significantly increased men’s interest in their own fertility. Although 75.3% of the participants indicated that viewing a video was useful, the percentage of participants who said that they would recommend the video to friends and acquaintances was 14.5% lower, at 60.8%. It has been reported that, when searching for information on sexual health, many young men prefer to look online (Tyler & Williams, 2014). As sex and reproduction are considered sensitive subjects, unobtrusive sources such as websites and apps, which enable information to be accessed using a smartphone, are preferred to paper media such as pamphlets (Bodin et al., 2018). This may explain the difference between the percentage of participants in the present study who found the video useful and the percentage who said that they would recommend it to friends and acquaintances.
A change was seen 2 weeks after the participants viewed the video for only one of the 13 behaviors: walking for approximately 5 min after sitting for approximately 1 hr. The number of participants who practiced this behavior increased by nine at the 2-week time point compared with before the video was viewed. A possible reason for the change seen in this behavior is that it was well defined and specific, and therefore easily incorporated into daily life.
Sedentary behavior is defined as waking time spent sitting or lying with low energy expenditure (≤ 1.5 metabolic equivalents) (Henson et al., 2023). The time spent engaged in sedentary behavior has increased for both adults and children as a result of changes in the economy, society, tourism, and technology. Such changes include increases in screen-based entertainment, the use of communication devices, and automobile transportation (Owen et al., 2014). The relationship between sedentary behavior and the risk of conditions such as chronic diseases (e.g., type 2 diabetes mellitus, cardiovascular disease, and obesity) and some types of cancer has been elucidated (Henson et al., 2023; Owen et al., 2014).
In Japan, the Guide to Physical Activity and Exercise for Good Health 2023 (Ministry of Health, Labour and Welfare, 2024) mentioned sedentary behavior in conjunction with everyday behaviors and exercise and included the recommendation that care be taken to avoid sedentary behavior for excessively long periods. Regarding sedentary behavior and male fertility, sitting for long periods warms the scrotum, thereby increasing the testicular temperature. The resulting oxidative stress damages sperm DNA, reducing fertilizability. Oxidative stress has become a major causal factor in male infertility (Durairajanayagam, 2018; Takeshima et al., 2020). In the present study, the median time spent sitting at work was 8 hr. The definition of sedentary behavior includes not only the time spent sitting, but also the time during which the level of energy expended for activities is low. Consequently, the study participants likely spent more than 8 hr per day engaged in sedentary behavior. A survey that compared sitting time in 20 countries showed that it was considerably longer in Japan than in other countries (Bauman et al., 2011). People of working age are less likely to exercise regularly, and those in occupations that involve prolonged periods of sitting, such as office workers, are likely to walk little, and their level of physical activity is likely to be low (Ministry of Health, Labour and Welfare, 2024). Interrupting sitting behavior for a period of time has been found to lead to moderate decreases in postprandial glucose, insulin, and triacylglycerol levels (Loh et al., 2020). In addition, infertile males with poor semen parameters have been found to have a higher prevalence of comorbidities, such as hypertension, hyperlipidemia, and hyperuricemia, than males who are not infertile. Consequently, sperm is regarded as an index of health (Shiraishi & Matsuyama, 2018). Because men’s health and the condition of their sperm are inextricably linked, education on fertility awareness should be provided in combination with that on male health. Providing men with information about the risks associated with sedentary behavior is thus a matter of particular urgency.
Motivation to Improve Lifestyle Behaviors and Fertility Awareness
Table 4 shows that the percentages of participants who were motivated to improve their lifestyle behaviors after viewing the video ranged from around 60% to 80%. The percentages with awareness of improvements in lifestyle behaviors at 2 weeks after viewing the video clearly decreased between around 30% and 40%. These findings indicate that, although the motivation to improve their lifestyle behaviors was high immediately after viewing the video, this did not result in continued awareness. The differences between motivation and the change in awareness were particularly large for the three items related to sleep quantity and quality, with a 39.1% decrease seen for refraining from smartphone use and game-playing before bedtime. The percentage of Japanese men who own smartphones is high: 93.1% for men in their 20s and 94.8% for those in their 30s (Ministry of Internal Affairs and Communications, 2024). The most common reason for using the internet is to communicate with friends (Ministry of Internal Affairs and Communications, 2024). Connecting and communicating with friends online is an important aspect of life and a means of alleviating stress. Nighttime smartphone use has been shown to disrupt circadian rhythms, prolong sleep latency, and reduce sleep quality (Krishnan et al., 2020; Ratan et al., 2021). Sleep quality and quantity are important to male fertility. With a nighttime sleep duration < 6 hr, the motility and forward progression rate of sperm have been found to decrease, and poor sleep quality has been shown to worsen the sperm count and forward progression rate (Chen et al., 2020). The number of participants who refrained from smartphone use or game-playing before bedtime increased from 13 before viewing the video to 26 at 2 weeks after viewing the video (Table 3). In addition, the number of participants exposed to outdoor sunlight after getting up in the morning increased by seven. Thus, an increase in the number of participants who adopted behaviors to improve sleep quality was observed. These findings indicate that men may change their behavior by addressing life challenges. Presenting a variety of options, starting from those that are feasible, so that they are incorporated into men’s lives, may enable them to improve their lifestyle behaviors. For example, even if the individual cannot completely stop using their smartphone after getting home, they can refrain from using it 30 min before bedtime. Thus, even if they cannot change their nighttime behavior, they can modify their morning behavior to get exposure to outdoor sunlight. The challenge is to continue providing further information and education so that the interest in fertility sparked by this video leads to specific behaviors.
In a study by Bodin et al. (2018), several men said that information on fertility awareness was irrelevant until it was time to conceive. In interviews conducted by Nakada-Nakagomi and Atogami (2025), men normally had little awareness of fertility in their daily life and first gained such awareness when pregnancy or marriage became imminent. Improving knowledge of male fertility and its associated risk factors improves not only male fertility, but also the general health and well-being of men (Krishnan et al., 2024). A systematic review of the literature suggested that, although the level of knowledge increased immediately after an intervention, achieving long-term knowledge of reproduction remains difficult (Krishnan et al., 2024).
When the change in lifestyle behavior awareness was analyzed by dividing the participants into those who normally engaged in the behaviors and those who did not, significant differences were seen for 7 of the 13 behaviors. This showed that the former group was more amenable to awareness enhancement, whereas the latter was resistant to a change in awareness. The greater amenability to enhanced awareness on the part of those who normally engaged in such behaviors may have been because they practiced these behaviors out of an awareness of the significance of lifestyle for maintaining and improving health, and because their keen awareness of health also made them amenable to strengthening that awareness further when the significance of fertility was added. By contrast, the findings showed the difficulty of educating individuals who did not normally engage in these lifestyle behaviors so that they could improve their behaviors. For both men and women, reproductive choices should be made based on adequate knowledge and information, as well as societal and environmental factors, health status, and timing. In regard to educational intervention, Krishnan et al. (2024) concluded that increasing fertility knowledge from youth is effective. Fertility education should therefore be provided to young people at school in an age-appropriate manner and to everyone of reproductive age (Harper et al., 2021). In the future, it will be necessary to provide fertility information to younger generations in parallel with educating reproductive-age men.
Thus, the following two specific recommendations are made. First, sex education in schools should include knowledge about fertility, age-related changes in eggs and sperm, and the relationship between fertility and lifestyle habits, as well as the need to prepare physically before becoming pregnant, accompanied by supporting evidence. Sex education in schools has focused on preventing unwanted pregnancy and sexually transmitted infections (Barron et al., 2022), but has not provided students with the knowledge they need to become pregnant. The key is to teach health education about pregnancy in relation to health management for junior and senior high school students. Second, motivational information should be given to prospective fathers, who should be encouraged to modify their behaviors based on this new knowledge (O’Brien et al., 2018). While efforts to improve preconception care for women are progressing, no such efforts are underway for men. As a result, men are not aware of the significant impact their own prepregnancy health has on their offspring (Rabiei et al., 2023).
The video shown in the present study sparked interest in fertility, and intervention methods to link this interest to behavior modification need to be investigated. One possible method is to bring more information to the attention of men, even if they do not intentionally seek it out, by means such as having health management centers at workplaces distribute email newsletters (Nakada-Nakagomi & Atogami, 2025) or public institutions disseminate videos. According to a report by So et al. (2025), men who have previously come into contact with information about male infertility are more likely to be interested in male infertility and undergo semen testing. Another method is to provide women with information about men’s prepregnancy health management, as men often obtain information about pregnancy and childbirth from their partners (Nakada-Nakagomi & Atogami, 2022). The above efforts may be useful in preventing and detecting male infertility early.
Remaining challenges include increasing men’s fertility awareness, engendering awareness that they are participants in fertility, and investigating approaches that can lead to behavioral modification even in men with little awareness of lifestyle behaviors and those not planning to get married or have children. It takes a long time to improve and establish lifestyle behaviors, so interventions should be considered as continuous rather than one-off involvement.
Limitations
The inclusion criteria in the present study were males in their 20s to 30s who could understand Japanese, were employed, and had no children. As a result, participants from other age groups and diverse cultural backgrounds were not included. In addition, the present study was an online survey, which could have resulted in selection bias. The participants were limited to those who use the internet, so caution is needed when generalizing the results to the general population. Although a follow-up survey was conducted after 2 weeks, there were many dropouts. Consequently, as a result of the straight-line cut, the sample size was smaller than required. Due to the possibility of a type II error due to the insufficient sample size, there is a possibility that a significant difference in the primary outcome could not be obtained. For secondary outcomes and subgroup analyses, the sample size was also small, so the study results may not fully capture the true effect of the intervention. To ensure the validity of the video content, it was created based on the advice of two experts. Video was chosen as the medium because many people in their 20s and 30s gather information from the internet and use video-streaming services. In this study, no pretest was conducted, so the empathy and interests of the men involved may not have been matched. There was also a limit to the risk factors that could be discussed, given the limited length of the video used in this study. Because DNA damage caused by oxidative stress in sperm is a major issue in male infertility, the video was created with the theme of improving sperm quality. Consequently, many other risk factors related to male fertility were not discussed. Further investigation is therefore needed in areas such as providing information on these other risk factors and education on specific preventive behaviors. Moreover, this study involved a single video intervention, and only one study showed behavioral change after 2 weeks. The reason for setting up a 2-week follow-up survey was to allow the participants to recall the content of the video when answering the questions 2 weeks later. Because the primary outcome of the video was to raise awareness of fertility and the contents were kept to a minimum, behavioral change was not expected and no long-term follow-up survey was conducted. A long-term study to determine whether behavior has been modified, along with an assessment of changes in lifestyle behavior over a long time span, with a sufficient sample size, is needed in the future.
Conclusion
In the present study, the viewing of an educational video focusing on improving sperm quality improved fertility awareness among men. An examination of lifestyle behaviors at 2 weeks after viewing the video showed a significant difference in only 1 of 13 behaviors: walking for approximately 5 min after sitting for approximately 1 hr. Our one-time video intervention temporarily motivated men to improve their lifestyle habits, but this motivation waned after 2 weeks. The participants who normally engaged in the lifestyle behaviors for health reasons were more likely to show a change in awareness regarding seven of the lifestyle behaviors for improved fertility after 2 weeks compared with those who did not engage in such behaviors. The evaluation results for the educational video showed that it was rated well in terms of understandability and interest, but the assessment of how well the video met participants’ expectations was low. Challenges remaining for the future include exploring continuous interventions that can motivate men to improve lifestyle behaviors that pose a risk to fertility, maintain their motivation, and encourage behavioral change.
Footnotes
Acknowledgements
The authors are grateful to the study participants for their cooperation in this study. The authors would also like to thank Yasushi Yumura, MD, professor of reproductive medicine at Yokohama City University Medical Center, and Prof. Sihoko Suzuki of the Kanagawa University of Human Services for their expert advice on creating the video used in this study. The authors would like to thank FORTE Science Communications (
) for English language editing.
Ethical Considerations
This study was approved by the Research Ethics Committee of the International University of Health and Welfare School of Health Sciences (No 23-Ig-210).
Consent to Participate
The participants provided informed consent online before participating in the study.
Consent for Publication
Not applicable.
Author Contributions
KN and FA conceived and designed the study. KN was in charge of coordinating with the Web research company, and the research data were delivered to KN as the principal investigator. KN was in charge of the statistical analysis, and KN and FA discussed the results of the analysis. Both authors contributed to the preparation of the final manuscript.
Funding
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was funded by a Grant-in-Aid for Scientific Research (C) 21K10894 from the Ministry of Education, Culture, Sports, Science and Technology.
Declaration of Conflicting Interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Data Availability Statement
The data sets used and/or analyzed during the current study area are available from the corresponding author on reasonable request.