Endometriosis is a chronic gynecological disease that affects various aspects of the women’s lives, so considering its impacts and improving health-promoting lifestyle is important. The present study aimed to determine the association between health-promoting lifestyle and endometriosis impacts on women lives.

This cross-sectional study was conducted on 200 women with endometriosis in the endometriosis clinic of Imam Reza Hospital in Mashhad-Iran. The data was collected using the HPLP-II (health-promoting lifestyle) and EIQ tools (endometriosis impact questionnaire), as well as socio-demographic and obstetrics characteristics questionnaires. Data was analyzed in SPSS 21 software. Spearman’s test was used to investigate the correlation between health-promoting behaviors and the impacts of endometriosis on women’s lives.

In the total of three recall periods of EIQ, there was a negative significant correlation between the overall lifestyle score of HPLP and the physical impact of endometriosis disease (r=-0.23; P < 0.001), the psychological impact (r=-0.29; P < 0.001), social impact (r=-0.30; P < 0.001), as well as education dimensions of EIQ (r=-0.52; P = 0.016).

Considering the negative significant correlation between the health-promoting lifestyle and the physical, psychological, social, as well as education impacts of endometriosis, adopting a healthy lifestyle for women with endometriosis seems useful and necessary. In future studies, it is recommended to provide information for writing a program with a clear and concise explanation for these women to improve affected women’s lives.

Endometriosis is a benign and chronic gynecological estrogen-dependent disease, which is defined as implantation of endometrial glands and stroma in a place other than the endometrial cavity of the uterus, causing a chronic inflammatory reaction in the pelvis. The most common replacement sites in the pelvic cavity include: ovary, uterosacral ligament and Douglas, cervix, sigmoid colon and pelvic peritoneum [1,2,3]. Endometriosis affects between 2 and 10% (190 million) of women and girls of reproductive age worldwide, but its prevalence in infertile women and in women with pain can even be up to 33% [4]. There are no accurate statistics of endometriosis in Iran, considering the younger population in Iran, it was estimated between 2 and 3 million women and maybe even a little more are affected. According to a study in Iran on 441 infertile women, the prevalence of endometriosis was 18.6% based on laparoscopy findings [5, 6]. Endometriosis may remain asymptomatic in some patients and be discovered accidentally [7, 8]. Affected women suffer from related symptoms such as infertility, periodic and non-periodic abdominal pain, painful menstruation, bloating, diarrhea or constipation, painful intercourse, painful urination, painful defecation [5, 9]. The etiology of endometriosis is complex and multifactorial [10]. The exact cause of endometriosis is still unclear, but retrograde menstruation is widely accepted as an crucial factor [11, 12].

The results of qualitative studies conducted to investigate the impact of the disease on the women lives have shown that endometriosis can affect various dimensions of their life, such as physical dimensions, sexual and marital relationships, psychological, social, economic, occupational, and employment and education, life style. Also, important opportunities in life, e.g. marriage, in other words, it has overshadowed their whole life [1, 13, 14]. Also studies have shown the negative impact of endometriosis on daily life and social well-being; general health; interpersonal interactions; productivity and self-esteem in affected women [15, 16]. The results of some studies have shown that endometriosis affects the psychological health of affected women and imposes a severe psychological burden on them. Affected women suffer from problems such as anxiety, depression, mood swings, sexual dysfunction and marital problems, so that psychological interventions can be suggested for them [17, 18].

The World Health Organization states that health promotion includes encouraging a healthy lifestyle, creating supportive environments for health and strengthening community performance, changing the direction of health services and creating optimal policies in public health [19]. A health-promoting lifestyle is the basis of a healthy and long-term life [20]. By emphasizing the slogan “health for all”, the health-promoting lifestyle can have a significant impact on improving the quality of life and increasing life expectancy and reducing health care costs [21]. Having a healthy lifestyle and exercising a health-promoting lifestyle should be considered as part of the main strategies for improving and maintaining health [22]. According to the definition of WHO, a health-promoting lifestyle is a real tendency towards improving and strengthening health and well-being and self-actualization [23]. Health-promoting lifestyle includes behaviors that require a positive approach to life and increases well-being and self-fulfillment. A health-promoting lifestyle prevents the occurrence of diseases and reduces their complications, and improves the quality of life [24]. Health-promoting life style are recognized as the main factors in maintaining and improving health. Considering the specificity of some health-related issues for women of reproductive age and also that the health of women of reproductive age affects their long-term health and that of their family members, especially their children, it is necessary to promote women’s health [25, 26]. Having healthy lifestyle is very important for all individuals, women with endometriosis are not exempt from this. According to the researches, it seems that participating in physical and occupational activities has been accompanied by changes in the synthesis of sex steroids, which may influence the risk of hormone-related diseases, such as endometriosis [27, 28]. Also, for example the results of some review studies showed the protective impact of consuming fruits and vegetables and the adverse impact of consuming beef and red meat, sausage and saturated fat [29, 30].

Considering that endometriosis is a chronic disease without definitive treatment that has significant impacts on women lives, it is necessary to investigate health-promoting behaviors and endometriosis impacts; in order to obtain more information to improve the lifestyle of affected women. Unfortunately, despite the fact that life with endometriosis is very disastrous for many women. The problems of them have not been considered much and women suffer from the harmful impacts for a long time [31]. Women with endometriosis face a world full of misinformation about their disease, taboos, and unanswered questions, lack of timely diagnosis and problematic treatments, which is covered with a painful, stubborn and chronic disease [14].

According to the review of the researcher in the field of improving a health-promoting lifestyle of women with endometriosis, the results show that there are few researches in this field. The results of experimental studies using the health promotion and health education model showed that there was a positive effect on improving the lifestyle of women with endometriosis and increased information to improve the lifestyle and reduce the pain caused by endometriosis. Therefore, adopting a healthy lifestyle for women with endometriosis seems useful and necessary [7, 9, 32].

In the current study, we intend to determine the relationship between health-promoting lifestyle and the impacts of endometriosis on the lives of women with endometriosis.

This descriptive-analytical cross-sectional study, which was done in 2022, recruited women at reproductive age (15–49 years), with endometriosis who referred to the endometriosis clinic of Imam Reza Hospital in Mashhad.

The study inclusion criteria were: women of reproductive age from 15 to 49 years with endometriosis, Diagnosis of endometriosis by open surgery or laparoscopy or histological diagnosis of endometriosis or the presence of endometrioma cyst and diagnosis by ultrasound and MRI and confirmation by a gynecologist, women with endometriosis in the pelvis and peritoneum, The onset of endometriosis symptoms at least one year, The absence of parietal endometriosis or endometriosis in remote organs, e.g. lungs and brain, Being Iranian, Being married, Literate to answer questions, Not being menopausal (amenorrhea for over a year), Not suffering from other major diseases, e.g. mental disorders, severe depression, schizophrenia or chronic diseases such as diabetes, kidney disease and rheumatology, Not suffering from cancer and any life-threatening diseases.

The results of studies have shown that there is no relationship between the severity of endometriosis or the stage of the disease and the severity of symptoms [33,34,35,36]. Therefore, in this study, women were not selected considering the stage of the disease as an inclusion criterion. The study exclusion criteria were: unwillingness to continue cooperation, incomplete completion of the questionnaire (failure to answer more than 10% of the questions).

The sample size was determined based on both specific objectives in the field of health-promoting lifestyle and disease impact. Based on the results of Abd-Elaziz et al.‘s study [9] and taking into account the largest standard deviation of the health-promoting lifestyle subdomains (SD = 3.74) for spiritual growth subdomain, α = 0.05, power = 90%, d = 0.05 was obtained around the mean (m = 15.32) equal to 186 women. Based on the results of Moradi et al.‘s study [37] and taking into account the largest standard deviation of disease impacts subdomains (SD = 32.7) for fertility subdomain, α = 0.05, power = 90%, d = 0.05, the mean of (m = 65.28) to 196 women were obtained. Considering that the sample size determined based on the variable of disease impact was more, therefore, the final sample size was considered to be 196 and rounded to 200 women.

The following formula was used to calculate the sample size:

The present study was confirmed by the Ethics Council of Mashhad University of Medical Sciences (ethics code: IR.MUMS.NURSE.REC.1401.064). Afterward data collection was started in the endometriosis clinic of Imam Reza Hospital in Mashhad. The researcher attended in the endometriosis clinic. Then, referring to the medical records of women with endometriosis, eligible women were invited to participate in the study. Women were selected through random sampling and considering the inclusion and exclusion criteria. After introducing herself to the patients and the necessary explanations about the purpose of the study, written questionnaires were provided to the patients and fulfilled by them after obtaining written and informed consent.

Data were collected by using HPLP-II (health-promoting lifestyle) questionnaire [38] and EIQ (Endometriosis Impact Questionnaire) tools [37] and also socio-demographic and obstetric characteristics questionnaires were made by the researcher includes age, education, occupation, income sufficiency for expenses, history of smoking/hookah, history of alcohol consumption, history of chronic disease, history of autoimmune disease, history of allergies, history of smoking/hookah, history of first degree relatives and their obstetrics and reproductive information.

The HPLP-II questionnaire is a standard questionnaire for examining health-promoting lifestyles, including 52 questions in 6 dimensions: nutrition, physical activity, spiritual growth, health responsibility, stress management, and interpersonal relationships. All items are scored from 1 to 4 (1 = never, 2 = sometimes, 3 = often, 4 = always) using a Likert scale [39]. This questionnaire was used many times in previous studies [9, 32, 40]. HPLP-II was translated from English into Persian, and its validity and reliability has been examined in earlier studies in Iran [25, 41]. The Cronbach’s of the HPLP-II questionnaire was reported as 0.87 in a study on an elderly population of 65 years or older [41].

Another tool that was used is EIQ, which was designed and psychometrically analyzed by Moradi et al. [37]. EIQ designed in Australia and it was used for the first time in Iran. The purpose of this tool is to measure the long-term impacts of chronic endometriosis on various aspects of women’s lives with endometriosis. This questionnaire contains 63 items that measure the impact of the disease on various aspects of the affected women’s lives in eight dimensions, including the impact of the disease on physical, psychological, social, marital intimacy and sexual relationships, fertility, occupational and financial aspects, education and the lifestyle in three time periods (last 12 months, 1 to 5 years ago and more than 5 years ago). Face, content and construct validity of this tool was conducted in Iran simultaneously with this study, in another study and confirmed by the research team. According to the results of face and content as well as construct validity. Impact Score with a score above 1.5 was approved. CVI and CVR values of the EIQ tool were 0.97 and 0.94, respectively. The Item to total Correlation confirmed the construct validity of all seven dimensions of tool, more than cut-off (0.3) except lifestyle. Cronbach’s alpha coefficient and Intra Correlation Coefficient (ICC) were acceptable for all dimensions [42].

Data was analyzed in SPSS 21 software. First, the normality of the data related to quantitative variables was examined using the Shapiro-Wilk test. Descriptive statistics including frequency (percentage), mean (standard deviation) in case of normal data and median (25th to 75th quartile) in case of non-normal data were used to describe socio-demographic characteristics, health promoting behaviors, and the impact of the disease and their relationship. Due to the non-normal distribution of the data of EIQ, Spearman’s test was used to investigate the correlation between health-promoting behaviors and the impacts of endometriosis.

In this study, 200 women with endometriosis were analyzed. The results of Table 1 shows the socio-demographic and obstetric characteristics of participants. The participant’s mean age was 35.6 years (SD: 6.2). In terms of the history of previous chronic diseases, 10 women (0.5%) had a positive report. Also, 17 (8.5%) women reported a history of autoimmune disease, of which 14 had hypothyroidism, one had rheumatoid arthritis and one person reported psoriasis. About one-third of women (35.5%) reported a history of allergies. There were 18 (0.9%) women with a history of endometriosis in first-degree relatives, of which 4 had a history of endometriosis in their mother’s and 7 women in their aunt’s, and 7 women in their sister’s (Table 1).

The mean (SD: standard deviation) of the overall score of health promoting behaviors was [2.49 (0.35)]. The participants scored the highest in the dimensions of interpersonal relationships [2.78 (0.38)], nutrition [2.71 (0.46)], and spiritual growth [2.68 (0.58)], health responsibility [2.46 (0.49)] and stress control [2.40 (0.48)] and had the lowest score in the dimension of physical activity [1.89 (0.61)] (Table 2).

In the total of three recall periods, the greatest impact of endometriosis disease was on the reproductive aspect of the participants with a mean (SD) of [47.7 (24.3)]. After that, the greatest impact of the disease was on physical [39.1 (18.7)], psychological [38.7 (21.7)], occupational and financial [33.8 (22.9)] and sexual relationships [33.6 (19.2)], education [27.7 (22.2)], social dimension [24.3 (23.8)] of affected women (Table 3).

In the total of three recall periods, there was a negative significant correlation between the overall lifestyle score and the physical impacts of endometriosis disease (r=-0.23; P < 0.001).

There was a negative significant correlation between the overall lifestyle score and the psychological impacts of endometriosis in the total of three recall periods (r=-0.29; P < 0.001).

In the total of three recall periods, there was a negative significant correlation between the overall lifestyle score and the social impacts of endometriosis disease (r=-0.30; P < 0.001).

There was no significant correlation between the overall score of lifestyle with the impacts of sexual relationships and marital intimacy and endometriosis in the total of three recall periods (r=-0.10; P = 0.269).

There was no significant correlation between the overall score of lifestyle with reproductive impacts and endometriosis in the total of three recall periods (r=-0.02; P = 0.754).

In the total of three recall periods, there was no significant negative correlation between the overall score of lifestyle with occupational and financial impacts of endometriosis disease (r=-0.18; P = 0.070).

In the total of three recall periods, there was a negative significant correlation between the overall lifestyle score with the impacts of endometriosis and education (r=-0.52; P = 0.016) (Table 4).

In this study, due to the non-normal distribution of the data, Spearman’s tests were used to investigate the correlation between health-promoting behaviors and the effects of endometriosis. Since the normality of the data is a necessary condition for performing linear regression, it was not possible to perform linear regression. On the other hand, performing logistic regression required the existence of a cut off in the EIQ tool, which is our dependent variable in this study, and this tool also does not have a cut off index; therefore, it was not possible to perform logistic regression.

The present study is the first study in Iran, which examined the health-promoting lifestyle and its relationships with the impact of endometriosis on women’s lives. According to the results of this study, regarding to status of health promoting lifestyle and its subscales (HPLP), women scored the most points in the subscales of interpersonal relationships, nutrition and spiritual growth. However, they obtained the lowest score in physical activity, which is consistent with findings from previous studies. Also, in the total of three recall periods of EIQ, there was a negative significant correlation between the overall lifestyle score and the physical impact of endometriosis disease, the psychological impact, social impact, as well as education impact of endometriosis disease.

According to the review of the researcher in the field of improving the lifestyle of women with endometriosis, the results showed that the researches in this field are few. Quantitative studies have been conducted to investigate the health-promoting lifestyle in women with endometriosis as an experimental trial with the model of health promotion and health education. The results showed a significant impact on improving the lifestyle of women with endometriosis and increased information to improve the lifestyle and reduce the pain caused by endometriosis in these patients [7, 32, 43]. The results of the qualitative studies conducted to investigate the impact of the endometriosis on women’s lives in Australia (2014) and Iran (2020) with the purpose of designing tools, showed that endometriosis can affect various aspects of women’s lives, such as physical aspects, sexual and marital relationships, psychological and social, economic, job and employment, and education [13, 14, 31, 44, 45]. In addition, numerous systematic reviews and narrative reviews have shown the impact of endometriosis on various aspects of women’s lives [46,47,48]. Based on the results of previous studies, it can be said that the negative impacts of endometriosis on the lives of affected women have been proven. But, unfortunately, despite the fact that life with endometriosis is very disastrous for many women. The problems of them have not been considered much and no constructive action has been taken to improve their health promotion lifestyle.

Similarly to the results of this study, the results of the others study such as, Iranian women of reproductive age [39] and university students [49, 50] as well as nurse in Washington [51], academic staff in Turkey [52] multi central study in medical student in turkey [53] scored the highest score in the spiritual growth, interpersonal relationships and nutrition domains. However, all the results of these studies obtained the lowest score in the physical activity domain that is consistent with the results of the present study. It may be due to a sedentary lifestyle, which is a challenge in most countries. The result of some studies of participants’ experiences revealed that lack of time, school or work duties, physical disability, family responsibilities, lack of preparation or motivation, environmental pressures, and financial constraints and costs were described as inhibiting factors for physical activity. Some of these inhibiting factors have also been reported in other qualitative studies [39, 54]. Risk factors such as physical inactivity, which is the cause of various diseases, are common among Iranian women. There are many evidences that regular physical activity leads to improvement in sleep patterns, relief of chronic pain, maintaining strength, coordination and balance needed to maintain daily life activities [39]. It is clear that the individuals must be responsible for their own health. To achieve this goal, they need to be informed about maintaining their health [53].

Also, regarding to the relationship between lifestyle and its subscales with the impact of endometriosis (EIQ) on different life dimensions of affected women in the total of three recall periods, (Last 12 months, 1–5 last years ago, More than 5 years ago), there was a negative significant correlation between the overall lifestyle score and the physical impacts of endometriosis disease. According to the research, it seems that participating in physical and occupational activities has been accompanied by changes in the synthesis of sex steroids and a decrease in the level of estrogen and an increase in globulins that bind to sex hormones, which may influence the risk of hormone-related diseases, such as endometriosis. Also, a lot of exercise can reduce the risk of disease by reducing the frequency of ovulation; because these factors, by increasing the amount of anti-inflammatory cytokines, can have a supportive impact in diseases with inflammatory processes and oxidative stress [27, 28]. Therefore, it is important to increase physical activity with educational program and providing facilities in this direction in women with endometriosis.

Regarding to the results of present study to subscales of HPLP, there was a negative significant correlation between the physical impacts of endometriosis and nutrition. The results of some review studies investigate the relationship between diet and endometriosis; showed the protective impact of consuming fruits and vegetables and the adverse impact of consuming beef and red meat, sausage and saturated fat. Poultry, fish, shellfish and eggs were not associated with the risk of endometriosis. A diet rich in vegetables and fruits contains high levels of vitamin C, carotenoids, folic acid and lycopene, and micronutrients that may help protect against cell proliferation. There is no significant relationship between the consumption of dairy products, liver, carrots, cheese, fish and grains with endometriosis. Fish oil capsules in combination with vitamin B₁₂ have been associated with positive impacts on endometriosis symptoms (especially dysmenorrhea). There is a potential link between hormonal and dietary factors and endometriosis. A diet rich in fat can increase undisputed estrogen levels. Therefore, to make general recommendations for a balanced and varied diet, more studies are needed to investigate the impact of nutrition on endometriosis [29, 30]. Caffeine, alcohol, and smoking can cause changes in the synthesis of known sex steroids, which may affect the risk of hormone-related diseases, such as endometriosis [55,56,57]. In general, it is recommended that women follow a healthy eating pattern in which fresh, unprocessed foods predominate and avoid consuming foods rich in carbohydrates or refined fats, salt, alcohol, and stimulant drinks [29]. In order to improve dietary patterns, appropriate changes should be made in knowledge, attitude, performance, in addition to the environment, food consumption. Improving the nutritional status as a primary prevention helps to improve health and performance and improves the quality of life at all ages. In general nutritional therapy as a secondary and tertiary prevention is an effective way to manage and control the disease, which reduces the risks of chronic disease, slows down the progress of the disease, and reduces its manifestations. Improving nutritional behavior not only helps women’s own health, but the evidence shows that improving the diet of women of reproductive age may be an important component of public health strategies aimed at reducing the burden of chronic disease in their generation [39]. Therefore, in the treatment of women with endometriosis, it is very important to consider the discussion on nutrition and to educate the correct method of nutrition and observe the correct diet pattern.

In the results of present study, regarding to subscales of HPLP, there was a negative significant correlation between the physical impact of endometriosis and spiritual growth, interpersonal relationships, stress control. Previous studies have shown that endometriosis can impact of interpersonal relationships, and stress control [46,47,48]. It means that perhaps by improving health-promoting behaviors, it is possible to influence the negative effects of the disease on physical impacts of endometriosis.

The results of some studies have shown that endometriosis affects the mental health of affected women and imposes a severe mental burden on them. Affected women suffer from problems such as anxiety, depression, mood swings, and reduced Life, sexual dysfunction and marital problems are faced, so that psychological interventions can be suggested for patients [17, 18]. In the results of present study in the total of three recall periods, there was a negative significant correlation between the overall lifestyle score and the psychological impacts of endometriosis disease. Also, there was a negative significant correlation between the psychological impacts of endometriosis with nutrition, physical activity, spiritual growth, interpersonal relationships and stress control. The results of some studies have shown that endometriosis affects the social dimension of affected women [46,47,48]. In the results of present study in the total of three recall periods, there was a negative significant correlation between the overall lifestyle score and the social impacts of endometriosis disease. Also, there was a negative significant correlation between the social impacts of endometriosis with physical activity, spiritual growth, and interpersonal relationships, as well as stress control. Therefore, it seems necessary to improve health-promoting behaviors in affected women of endometriosis, to influence the negative effects of endometriosis on psychological and social dimensions. The results of the studies showed that endometriosis has a negative impact on educational dimension of women’s lives [1, 14, 48, 58]. In the total of three recall periods, there was a negative significant correlation between the overall lifestyle score with the impacts of endometriosis and education. Also, there was a negative significant correlation between the impacts of endometriosis and education with spiritual growth and interpersonal relationships. It was due to this fact that may be not having a healthy lifestyle has a negative impact on educational status; on the other hand the high costs of diagnosis and treatment or infertility treatment is an obstacle to provide enough necessities for optimal healthy life style.

In this study two valid tools were used to collect the data. All women had a valid diagnosis of endometriosis by a gynecologist colleague who is the head of Mashhad endometriosis clinic (L.H). One of the weakness of this study was the large number of questions. In general, many studies have shown the adverse impacts of endometriosis on various aspects on the women’s lives, and many studies have examined the quality of life of affected women. The distinguishing feature of the present study is to examine the relationship between the health-promoting lifestyle, its subscales, and impacts of the endometriosis with its chronic nature on different dimensions of affected women. The purpose of the study is to highlight the effect of strengthening health-promoting lifestyle on improving the negative impacts of endometriosis. Let’s not only provide evidence but also help these women complications constructively.

Our results showed that in the total of three recall periods, there was a negative significant correlation between the overall lifestyle score and the physical, psychological, social, as well as education impacts of endometriosis. Overall, although endometriosis is a chronic disease that has a significant and severe impacts on the lives of affected women. The research conducted on the care and health promotion of women with endometriosis is very limited. Improving the health and promoting the well-being of women with endometriosis, through constructive strategy that improve a healthy lifestyle in women, can be useful. Medical staff, e.g. midwives and nurses, play an important role in providing optimal and comprehensive care for chronic diseases such as endometriosis. They can play an important role in providing educational and health services. Treatment staff can help patients with disease-related practical training so that patients can make more informed decisions about maintaining their health. In this context, we can facilitate the development and implementation of a treatment program by identifying the specific problems and needs and preferences related to the disease of the affected women, which can even be developed jointly between the treatment practitioners and the patient.

In future studies, it is recommended to conduct studies with more robust methodology and larger sample size in various communities with different sociocultural contexts to achieve more generalizable results with the aim of providing information in a written program with a clear and concise explanation to improve affected women’s lives based on health-promoting lifestyle.

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All authors participated in the editing of this manuscript and approved the final version for publication. All authors jointly planned and designed the study. SM identified potential participants and recruited the participants. SM and MM have made substantial contributions to the conception and design, acquisition of data, analysis, and interpretation of data. KH. M and T. KH have made substantial contributions to conception and design. All authors have been involved in drafting the manuscript or revising it critically for important intellectual content. All authors read and approved the final manuscript.

Correspondence to Sanaz Mollazadeh.

The present study was confirmed by the Ethics Council of Mashhad University of Medical Sciences (ethics code: IR.MUMS.NURSE.REC. 1401.064). All methods were carried out in accordance with relevant guidelines and regulations in the declaration of Helsinki. The researcher invited eligible and willing women to participate in the study after obtaining written and informed consent from all subjects and/or their legal guardian(s).

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The authors declare no competing interests.

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