Objective: To give an historical record of the research of the World Health Organization (WHO) Task Force to develop methods of male contraception; to examine the social, political, medical, pharmaceutical, funding, a...Objective: To give an historical record of the research of the World Health Organization (WHO) Task Force to develop methods of male contraception; to examine the social, political, medical, pharmaceutical, funding, and other factors that influenced progress; and to suggest reasons why such methods are only now becoming available. Design: Review of basic and clinical research over 30 years. Setting: Task force of a multinational agency and collaborating agencies. Conclusion(s): Through the involvement of many international scientists, the WHO Task Force has uniquely contributed to the exploratory phases of the research in male contraception and by its multicenter contraceptive efficacy studies has accelerated progress towards the ideal hormonal method. Despite an adverse climate involving social and political attitudes, funding constraints, and pharmaceutical industry hesitations, WHO formed coalitions with governments and international agencies to sustain research with results that apply to men in culturally diverse populations and thereby to influence activities across the whole range of global reproductive health and family planning.展开更多
Sex has always been a taboo subject in Asian society. However, over the past few years, awareness in the field of men＇s sexual health has improved, and interest in sexual health research has recently increased. The e...Sex has always been a taboo subject in Asian society. However, over the past few years, awareness in the field of men＇s sexual health has improved, and interest in sexual health research has recently increased. The epidemiology and prevalence of erectile dysfunction, hypogonadism and premature ejaculation in Asia are similar in the West. However, several issues are specific to Asian males, including culture and beliefs, awareness, compliance and the availability of traditional/complementary medicine. In Asia, sexual medicine is still in its infancy, and a concerted effort from the government, relevant societies, physicians and the media is required to propel sexual medicine to the forefront of health care.展开更多
Infertility is a common condition experienced by many men and women, and treatments are expensive. The World Health Organization and American Society of Reproductive Medicine define infertility as a disease, yet priva...Infertility is a common condition experienced by many men and women, and treatments are expensive. The World Health Organization and American Society of Reproductive Medicine define infertility as a disease, yet private companies infrequently offer insurance coverage for infertility treatments. This is despite the clear role that healthcare insurance plays in ensuring access to care and minimizing the financial burden of expensive services. In this review, we assess the current knowledge of how male infertility care is covered by insurance in the United States. We begin with an appraisal of the costs of male infertility care, then examine the state insurance laws relevant to male infertility, and close with a discussion of why insurance coverage for male infertility is important to both men and women. Importantly, we found that despite infertility being classified as a disease and males contributing to almost half of all infertility cases, coverage for male infertility is often excluded from health insurance laws. Excluding coverage for male infertility places an undue burden on their female partners. In addition, excluding care for male infertility risks missing opportunities to diagnose important health conditions and identify reversible or irreversible causes of male infertility. Policymakers should consider providing equal coverage for male and female infertility care in future health insurance laws.展开更多
There has been little focus on men＇s reproductive health （RH） in China. This descriptive study conducted in Yiling District, Yichang, China, surveyed male knowledge of sexual physiology and RH to assess levels of k...There has been little focus on men＇s reproductive health （RH） in China. This descriptive study conducted in Yiling District, Yichang, China, surveyed male knowledge of sexual physiology and RH to assess levels of knowledge, attitudes and practices （KAPs） regarding prevention of sexually transmitted diseases （STDs）. A total of 3933 men, aged 18-59 years （mean, 40.3 years）, were recruited by cluster random sampling. They completed a questionnaire in the presence of an interviewer, with items related to subject characteristics, RH knowledge, and subjective symptoms of the reproductive system. Physical examination and reproductive system disease diagnosis were performed. Participants＇ occupations were predominantly skilled labor （80.5%）. Nearly four-fifths （78.5%） respondents had at least one reproductive disease. Over half of respondents were aware of and declared a positive attitude about sexual physiology and safe sex, and 70% of them selected to visit a doctor when they had a reproductive disorder. However, only 41.9% believed human immunodeficiency virus/acquired immunodeficiency syndrome could be transmitted through breastfeeding, and 64.6% incorrectly thought they could avoid contracting STDs by cleaning their genitals after intercourse. In addition, 45% discriminated against and were unwilling to be friends with infected persons. Nearly 45% of those with a reproductive system disorder refused to discuss it with friends or family members. These results indicate that this cohort of Chinese men had a certain degree of KAP about RH, whereas some aspects require further public health education in the general population. It is necessary to disseminate accurate knowledge of STD risk in China based on sociodemographic characteristics.展开更多
Here we review the international evidence for benefits and risks of infant male circumcision (MC) and use this to develop an evidence-based policy statement for a developed nation setting, focusing on Australia. Evide...Here we review the international evidence for benefits and risks of infant male circumcision (MC) and use this to develop an evidence-based policy statement for a developed nation setting, focusing on Australia. Evidence from good quality studies that include meta-analyses and randomized controlled trials showed that MC provides strong protection against: urinary tract infections and, in infancy, renal parenchymal disease;phimosis;paraphimosis;balanoposthitis;foreskin tearing;some heterosexually transmitted infections including HPV, HSV-2, trichomonas, HIV, and genital ulcer disease;thrush;inferior hygiene;penile cancer and possibly prostate cancer. In women, circumcision of the male partner protects against HPV, HSV-2, cervical cancer, bacterial vaginosis, and possibly Chlamydia. MC has no adverse effect on sexual function, sensitivity, penile sensation or satisfaction and may enhance the male sexual experience. Adverse effects are uncommon (<1%), and virtually all are minor and easily treated. For maximum benefits, safety, convenience and cost savings, MC should be performed in infancy and with local anesthesia. A risk-benefit analysis shows benefits exceed risks by a large margin. Over their lifetime up to half of uncircumcised males will suffer a medical condition as a result of retaining their foreskin. The ethics of infant MC and childhood vaccination are comparable. Our analysis finds MC is beneficial, safe and cost-effective, and should optimally be performed in infancy. In the interests of public health and individual wellbeing, adequate parental education, and steps to facilitate access and affordability should be encouraged in developed countries.展开更多
Objective To study the effects of Cow＇s milk on the reproduction in male mice. Methods Twenty-four male mice were divided randomly into two groups： milk group （M） and control group （C）. Each mouse was given 10 m...Objective To study the effects of Cow＇s milk on the reproduction in male mice. Methods Twenty-four male mice were divided randomly into two groups： milk group （M） and control group （C）. Each mouse was given 10 mL milk per day from 4 to 16 weeks in the group M. At the age of 17 weeks, all the mice were sacrificed. Results Serum testosterone was decreased in the group M （P=0.037）. No significant difference was found in weight of testes, seminal vesicle or adrenal gland of mice between the groups C and M. However, the weight of seminal vesicle decreased when expressed in g/100 g body weight in the group M. Epididymal sperm concentration, motility, morphology, and sperm head number were not affected by milk. Conclusion Cow＇s milk has adverse effects on the reproductive system in ICR male mice. Further studies are needed to clarify the specific effects of milk on reproductive health.展开更多
The incidence of male reproductive failure leading to infertility, whether due to delayed parenthood, environmental issues, genetic factors, drugs, etc., is increasing throughout the world. The diagnosis and prognosis...The incidence of male reproductive failure leading to infertility, whether due to delayed parenthood, environmental issues, genetic factors, drugs, etc., is increasing throughout the world. The diagnosis and prognosis of male subfertility have become a challenge. While the basic semen assessment has been performed for many years, a number of studies question the value of the traditional semen characteristics. This is partly due to inadequate methods and standardization, limited knowledge of technical requirements for quality assurance, and an incomplete understanding of what clinical information a semen assessment can provide. Laboratories currently performing semen and endocrine assessment show great variability. The World Health Organization （WHO） manual for the evaluation of semen has been the core of andrology and fertility evaluation that has helped in further development of this field over many years. These include the physical appearance of the ejaculate, assessments of sperm count, motility, vitality, morphology, and functional aspects of the sperm and semen sample. These tests also include male endocrine profile, biochemical evaluation of the semen, detection of antisperm antibodies in serum, the use of computer-aided sperm analysis （CASA）, sperm DNA integrity, and its damage due to oxidative stress. Assisted reproductive techniques （e.g., IVF, ICSI） have shown great success but are too expensive. Further development in this field with newer techniques and extensive training/instructions can improve accuracy and reduce variability, thus maintaining the quality and standards of such an evaluation. There is an urgent need to have standardized training centers and increased awareness in this area of men＇s health for reproductive success.展开更多
This study investigated the effects of varicocele on semen parameters in infertile men based on the new 2010 World Health Organization laboratory manual for the examination of human semen. Semen analysis results （vol...This study investigated the effects of varicocele on semen parameters in infertile men based on the new 2010 World Health Organization laboratory manual for the examination of human semen. Semen analysis results （volume, sperm count, motility, and morphology） were the primary outcomes. An electronic search to collect the data was conducted using the Medline/PubMed, SJU discover, and Google Scholar databases. We searched articles published from 2010 to August 2015, i.e., after the publication of the 2010 WHO manual. We included only those studies that reported the actual semen parameters of adult infertile men diagnosed with clinical varicocele and contained a control group of either fertile men or normozoospermic men who were not diagnosed with varicocele. Ten studies were included in the meta-analysis, involving 1232 men. Varicocele was associated with reduced sperm count （mean difference： -44.48 x 106 ml-1; 95% Ch -61.45, -27.51 x 106 ml-1; P〈 0.001）, motility （mean difference： -26.67%; 95% Ch -34.27, -19.08; P 〈 0.001）, and morphology （mean difference： -19.68%; 95% Ch -29.28, -10.07; P 〈 0.001） but not semen volume （mean difference： -0.23 ml; 95% CI： -0.64, 0.17）. Subgroup analyses indicated that the magnitude of effect was influenced by control subtype but not WHO laboratory manual edition used for semen assessment. We conclude that varicocele is a significant risk factor that negatively affects semen quality, but the observed pooled effect size on semen parameters does not seem to be affected by the WHO laboratory manual edition. Given most of the studies published after 2010 still utilized the 1999 manual for semen analysis, further research is required to fully understand the clinical implication of the 2010 WHO laboratory manual on the association between varicocele and semen parameters.展开更多
Men＇s health concerns have evolved from the traditional andrology and male sexual health to a more holistic approach that encompasses male psychological, social and physical health. The poor state of health in men co...Men＇s health concerns have evolved from the traditional andrology and male sexual health to a more holistic approach that encompasses male psychological, social and physical health. The poor state of health in men compared to their female counterparts is well documented. A review of the epidemiological data from Malaysia noted a similar trend in which men die at higher rates in under 1 and above 15 years old groups and most disease categories compared to women. In Malaysia, the main causes of death in men are non-communicable diseases and injuries. Risk factors, such as risk-taking behaviour, smoking and hypertension, are prevalent and amenable to early interventions. Erectile dysfunction, premature ejaculation and prostate disorders are also prevalent. However, many of these morbidities go unreported and are not diagnosed early; therefore, opportunities for early intervention are missed. This reflects poor health knowledge and inadequate health-care utilisation among Malaysian men. Their health-seeking behaviour has been shown to be strongly influenced by family members and friends. However, more research is needed to identify men＇s unmet health-care needs and to develop optimal strategies for addressing them. Because the Malaysian population is aging and there is an increase in sedentary lifestyles, optimizing men＇s health will remain a challenge unless effective measures are implemented. The existing male-unfriendly health-care system and the negative influence of masculinity on men＇s health behaviour must be addressed. A national men＇s health policy based on a male-friendly approach to health-care delivery is urgently needed to provide a framework for addressing these challenges.展开更多
Background: There are various health problems in rotating shift workers. There have been few studies on the associations of male climacteric symptoms with duration of working and lifestyle. Objective: The aim of this ...Background: There are various health problems in rotating shift workers. There have been few studies on the associations of male climacteric symptoms with duration of working and lifestyle. Objective: The aim of this study was to determine the differences in male climacteric symptoms depending on the number of working years and to determine whether lifestyle habits differ depending on the number of working years in rotating shift workers. Methods: We collected participant’s data from the manufacturing companies in Japan during the period from March to May in 2017. We conducted a self-administered questionnaire survey in 1561 male rotating night shift workers. Male climacteric symptoms were evaluated by using the Aging Males’ Symptoms (AMS) rating scale. We analyzed 636 rotating shift workers aged over 40 years old whose all AMS data was collected. Results: A significant difference in psychological AMS score was found between men who had worked for 10 - 19 years (9.4 ± 3.9) and men who had worked for more than 40 years (7.6 ± 3.0) (p = 0.011). Sexual functional AMS score significantly differed depending on the number of working years (less than 10 years: 8.1 ± 3.9, 10 - 19 years: 9.8 ± 4.1, 20 - 29 years: 7.9 ± 3.3, 30 - 39 years: 9.3 ± 3.5, more than 40 years: 9.3 ± 3.5) (p < 0.001). The proportion of workers with a balanced meal intake was significantly lower in men who had worked for less than 10 years and the proportions of such workers were significantly higher in men who had worked for 10 - 19 years and for more than 40 years. The proportions of men who did not drink alcohol were high in men who had worked for less than 10 years and 20 - 29 years and low in men who had worked more than 30 years. Conclusion: Psychological AMS score and sexual functional AMS score are significantly different among the 5 groups according to the number of working years on rotating shift. In addition, well-balanced diet on day shift and reduction of alcohol drinking is a related-factor for long-term rotating night shift workers.展开更多
文摘Objective: To give an historical record of the research of the World Health Organization (WHO) Task Force to develop methods of male contraception; to examine the social, political, medical, pharmaceutical, funding, and other factors that influenced progress; and to suggest reasons why such methods are only now becoming available. Design: Review of basic and clinical research over 30 years. Setting: Task force of a multinational agency and collaborating agencies. Conclusion(s): Through the involvement of many international scientists, the WHO Task Force has uniquely contributed to the exploratory phases of the research in male contraception and by its multicenter contraceptive efficacy studies has accelerated progress towards the ideal hormonal method. Despite an adverse climate involving social and political attitudes, funding constraints, and pharmaceutical industry hesitations, WHO formed coalitions with governments and international agencies to sustain research with results that apply to men in culturally diverse populations and thereby to influence activities across the whole range of global reproductive health and family planning.
文摘Sex has always been a taboo subject in Asian society. However, over the past few years, awareness in the field of men＇s sexual health has improved, and interest in sexual health research has recently increased. The epidemiology and prevalence of erectile dysfunction, hypogonadism and premature ejaculation in Asia are similar in the West. However, several issues are specific to Asian males, including culture and beliefs, awareness, compliance and the availability of traditional/complementary medicine. In Asia, sexual medicine is still in its infancy, and a concerted effort from the government, relevant societies, physicians and the media is required to propel sexual medicine to the forefront of health care.
文摘Infertility is a common condition experienced by many men and women, and treatments are expensive. The World Health Organization and American Society of Reproductive Medicine define infertility as a disease, yet private companies infrequently offer insurance coverage for infertility treatments. This is despite the clear role that healthcare insurance plays in ensuring access to care and minimizing the financial burden of expensive services. In this review, we assess the current knowledge of how male infertility care is covered by insurance in the United States. We begin with an appraisal of the costs of male infertility care, then examine the state insurance laws relevant to male infertility, and close with a discussion of why insurance coverage for male infertility is important to both men and women. Importantly, we found that despite infertility being classified as a disease and males contributing to almost half of all infertility cases, coverage for male infertility is often excluded from health insurance laws. Excluding coverage for male infertility places an undue burden on their female partners. In addition, excluding care for male infertility risks missing opportunities to diagnose important health conditions and identify reversible or irreversible causes of male infertility. Policymakers should consider providing equal coverage for male and female infertility care in future health insurance laws.
文摘There has been little focus on men＇s reproductive health （RH） in China. This descriptive study conducted in Yiling District, Yichang, China, surveyed male knowledge of sexual physiology and RH to assess levels of knowledge, attitudes and practices （KAPs） regarding prevention of sexually transmitted diseases （STDs）. A total of 3933 men, aged 18-59 years （mean, 40.3 years）, were recruited by cluster random sampling. They completed a questionnaire in the presence of an interviewer, with items related to subject characteristics, RH knowledge, and subjective symptoms of the reproductive system. Physical examination and reproductive system disease diagnosis were performed. Participants＇ occupations were predominantly skilled labor （80.5%）. Nearly four-fifths （78.5%） respondents had at least one reproductive disease. Over half of respondents were aware of and declared a positive attitude about sexual physiology and safe sex, and 70% of them selected to visit a doctor when they had a reproductive disorder. However, only 41.9% believed human immunodeficiency virus/acquired immunodeficiency syndrome could be transmitted through breastfeeding, and 64.6% incorrectly thought they could avoid contracting STDs by cleaning their genitals after intercourse. In addition, 45% discriminated against and were unwilling to be friends with infected persons. Nearly 45% of those with a reproductive system disorder refused to discuss it with friends or family members. These results indicate that this cohort of Chinese men had a certain degree of KAP about RH, whereas some aspects require further public health education in the general population. It is necessary to disseminate accurate knowledge of STD risk in China based on sociodemographic characteristics.
文摘Here we review the international evidence for benefits and risks of infant male circumcision (MC) and use this to develop an evidence-based policy statement for a developed nation setting, focusing on Australia. Evidence from good quality studies that include meta-analyses and randomized controlled trials showed that MC provides strong protection against: urinary tract infections and, in infancy, renal parenchymal disease;phimosis;paraphimosis;balanoposthitis;foreskin tearing;some heterosexually transmitted infections including HPV, HSV-2, trichomonas, HIV, and genital ulcer disease;thrush;inferior hygiene;penile cancer and possibly prostate cancer. In women, circumcision of the male partner protects against HPV, HSV-2, cervical cancer, bacterial vaginosis, and possibly Chlamydia. MC has no adverse effect on sexual function, sensitivity, penile sensation or satisfaction and may enhance the male sexual experience. Adverse effects are uncommon (<1%), and virtually all are minor and easily treated. For maximum benefits, safety, convenience and cost savings, MC should be performed in infancy and with local anesthesia. A risk-benefit analysis shows benefits exceed risks by a large margin. Over their lifetime up to half of uncircumcised males will suffer a medical condition as a result of retaining their foreskin. The ethics of infant MC and childhood vaccination are comparable. Our analysis finds MC is beneficial, safe and cost-effective, and should optimally be performed in infancy. In the interests of public health and individual wellbeing, adequate parental education, and steps to facilitate access and affordability should be encouraged in developed countries.
文摘Objective To study the effects of Cow＇s milk on the reproduction in male mice. Methods Twenty-four male mice were divided randomly into two groups： milk group （M） and control group （C）. Each mouse was given 10 mL milk per day from 4 to 16 weeks in the group M. At the age of 17 weeks, all the mice were sacrificed. Results Serum testosterone was decreased in the group M （P=0.037）. No significant difference was found in weight of testes, seminal vesicle or adrenal gland of mice between the groups C and M. However, the weight of seminal vesicle decreased when expressed in g/100 g body weight in the group M. Epididymal sperm concentration, motility, morphology, and sperm head number were not affected by milk. Conclusion Cow＇s milk has adverse effects on the reproductive system in ICR male mice. Further studies are needed to clarify the specific effects of milk on reproductive health.
文摘The incidence of male reproductive failure leading to infertility, whether due to delayed parenthood, environmental issues, genetic factors, drugs, etc., is increasing throughout the world. The diagnosis and prognosis of male subfertility have become a challenge. While the basic semen assessment has been performed for many years, a number of studies question the value of the traditional semen characteristics. This is partly due to inadequate methods and standardization, limited knowledge of technical requirements for quality assurance, and an incomplete understanding of what clinical information a semen assessment can provide. Laboratories currently performing semen and endocrine assessment show great variability. The World Health Organization （WHO） manual for the evaluation of semen has been the core of andrology and fertility evaluation that has helped in further development of this field over many years. These include the physical appearance of the ejaculate, assessments of sperm count, motility, vitality, morphology, and functional aspects of the sperm and semen sample. These tests also include male endocrine profile, biochemical evaluation of the semen, detection of antisperm antibodies in serum, the use of computer-aided sperm analysis （CASA）, sperm DNA integrity, and its damage due to oxidative stress. Assisted reproductive techniques （e.g., IVF, ICSI） have shown great success but are too expensive. Further development in this field with newer techniques and extensive training/instructions can improve accuracy and reduce variability, thus maintaining the quality and standards of such an evaluation. There is an urgent need to have standardized training centers and increased awareness in this area of men＇s health for reproductive success.
文摘This study investigated the effects of varicocele on semen parameters in infertile men based on the new 2010 World Health Organization laboratory manual for the examination of human semen. Semen analysis results （volume, sperm count, motility, and morphology） were the primary outcomes. An electronic search to collect the data was conducted using the Medline/PubMed, SJU discover, and Google Scholar databases. We searched articles published from 2010 to August 2015, i.e., after the publication of the 2010 WHO manual. We included only those studies that reported the actual semen parameters of adult infertile men diagnosed with clinical varicocele and contained a control group of either fertile men or normozoospermic men who were not diagnosed with varicocele. Ten studies were included in the meta-analysis, involving 1232 men. Varicocele was associated with reduced sperm count （mean difference： -44.48 x 106 ml-1; 95% Ch -61.45, -27.51 x 106 ml-1; P〈 0.001）, motility （mean difference： -26.67%; 95% Ch -34.27, -19.08; P 〈 0.001）, and morphology （mean difference： -19.68%; 95% Ch -29.28, -10.07; P 〈 0.001） but not semen volume （mean difference： -0.23 ml; 95% CI： -0.64, 0.17）. Subgroup analyses indicated that the magnitude of effect was influenced by control subtype but not WHO laboratory manual edition used for semen assessment. We conclude that varicocele is a significant risk factor that negatively affects semen quality, but the observed pooled effect size on semen parameters does not seem to be affected by the WHO laboratory manual edition. Given most of the studies published after 2010 still utilized the 1999 manual for semen analysis, further research is required to fully understand the clinical implication of the 2010 WHO laboratory manual on the association between varicocele and semen parameters.
文摘Men＇s health concerns have evolved from the traditional andrology and male sexual health to a more holistic approach that encompasses male psychological, social and physical health. The poor state of health in men compared to their female counterparts is well documented. A review of the epidemiological data from Malaysia noted a similar trend in which men die at higher rates in under 1 and above 15 years old groups and most disease categories compared to women. In Malaysia, the main causes of death in men are non-communicable diseases and injuries. Risk factors, such as risk-taking behaviour, smoking and hypertension, are prevalent and amenable to early interventions. Erectile dysfunction, premature ejaculation and prostate disorders are also prevalent. However, many of these morbidities go unreported and are not diagnosed early; therefore, opportunities for early intervention are missed. This reflects poor health knowledge and inadequate health-care utilisation among Malaysian men. Their health-seeking behaviour has been shown to be strongly influenced by family members and friends. However, more research is needed to identify men＇s unmet health-care needs and to develop optimal strategies for addressing them. Because the Malaysian population is aging and there is an increase in sedentary lifestyles, optimizing men＇s health will remain a challenge unless effective measures are implemented. The existing male-unfriendly health-care system and the negative influence of masculinity on men＇s health behaviour must be addressed. A national men＇s health policy based on a male-friendly approach to health-care delivery is urgently needed to provide a framework for addressing these challenges.
文摘Background: There are various health problems in rotating shift workers. There have been few studies on the associations of male climacteric symptoms with duration of working and lifestyle. Objective: The aim of this study was to determine the differences in male climacteric symptoms depending on the number of working years and to determine whether lifestyle habits differ depending on the number of working years in rotating shift workers. Methods: We collected participant’s data from the manufacturing companies in Japan during the period from March to May in 2017. We conducted a self-administered questionnaire survey in 1561 male rotating night shift workers. Male climacteric symptoms were evaluated by using the Aging Males’ Symptoms (AMS) rating scale. We analyzed 636 rotating shift workers aged over 40 years old whose all AMS data was collected. Results: A significant difference in psychological AMS score was found between men who had worked for 10 - 19 years (9.4 ± 3.9) and men who had worked for more than 40 years (7.6 ± 3.0) (p = 0.011). Sexual functional AMS score significantly differed depending on the number of working years (less than 10 years: 8.1 ± 3.9, 10 - 19 years: 9.8 ± 4.1, 20 - 29 years: 7.9 ± 3.3, 30 - 39 years: 9.3 ± 3.5, more than 40 years: 9.3 ± 3.5) (p < 0.001). The proportion of workers with a balanced meal intake was significantly lower in men who had worked for less than 10 years and the proportions of such workers were significantly higher in men who had worked for 10 - 19 years and for more than 40 years. The proportions of men who did not drink alcohol were high in men who had worked for less than 10 years and 20 - 29 years and low in men who had worked more than 30 years. Conclusion: Psychological AMS score and sexual functional AMS score are significantly different among the 5 groups according to the number of working years on rotating shift. In addition, well-balanced diet on day shift and reduction of alcohol drinking is a related-factor for long-term rotating night shift workers.
