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Relationships among Type-D Personality, Fatigue, and Quality of Life in Infertile Women

  • Ju-Hee Nho
    Correspondence
    Correspondence to: Ju-Hee Nho, College of Nursing, Research Institute of Nursing Science, Jeonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonjusi, Jeollabukdo, 54896, Republic of Korea.
    Affiliations
    College of Nursing, Jeonbuk National University, Republic of Korea

    Research Institute of Nursing Science, Jeonbuk National University, Republic of Korea
    Search for articles by this author
  • Eun Jin Kim
    Affiliations
    College of Nursing, Jeonbuk National University, Republic of Korea
    Search for articles by this author
Open AccessPublished:August 11, 2022DOI:https://doi.org/10.1016/j.anr.2022.08.001

      Summary

      Purpose

      The objective of the present study was to investigate the prevalence of the type-D personality and identify the relationship between type-D personality, fatigue, and quality of life (QoL) in infertile women.

      Methods

      A total of 149 infertile women were recruited between October 2020 and January 2021. The participants were assessed through self-administered questionnaires using the type- D personality scale-14, fatigue severity scale, and fertility QoL instrumental questionnaire. Data were analyzed using the independent t-test, chi-square test, Pearson's correlation coefficients, and multiple regression analysis using the SPSS/WIN 25.0 program for Windows.

      Results

      Approximately 40.9% of infertile women were classified into the type-D personality group, which showed significantly higher fatigue and lower QoL than the non-type-D personality group. Fatigue was the most influential factor on the QoL of infertile women (β = −.23, p = .003), followed by the duration of infertility treatment (β = −.22, p = .003), type-D personality (β = −.18, p = .025), and relationship with spouse (β = −.17, p = .024). These variables account for approximately 22% of the variance.

      Conclusions

      Intervention programs that consider fatigue, type-D personality, relationship with spouses, and treatment duration may be useful for improving QoL in infertile women.

      Keywords

      Introduction

      In general, infertility is defined as the inability to conceive after 1 year or longer of unprotected sexual intercourse [

      Centers for Disease Control and Prevention. Reproductive health: infertility [Internet]. Atlanta: Centers for Disease Control and Prevention [cited 2022 May 9]. Available from: http://www.cdc.gov/reproductivehealth/infertility/index.htm#:∼:text=What%20is%20 infertility%3F,6%20months%20of%20unprotected%20sex.

      ]. About 19% of married women aged 15–49 years in the United States report being unable to conceive even after one year of trying [

      Centers for Disease Control and Prevention. Reproductive health: infertility [Internet]. Atlanta: Centers for Disease Control and Prevention [cited 2022 May 9]. Available from: http://www.cdc.gov/reproductivehealth/infertility/index.htm#:∼:text=What%20is%20 infertility%3F,6%20months%20of%20unprotected%20sex.

      ]. Among 1,289 married women aged 15–49 years in South Korea, 52.1% experienced infertility [
      • Statistics Korea
      Regional indicators: whether a married woman (ages 15-49) has experienced infertility diagnosis.
      ]. Despite the increased cost of treating infertility, the domestic fertility rate remains low [
      • Statistics Korea
      Regional indicators: total fertility rate.
      ]. Among the Organization for Economic Cooperation and Development (OECD) member countries, South Korea has the lowest fertility rate (.84 in 2020, compared to 1.64 in the United States, 1.70 in China, 1.33 in Japan, and 1.24 in Italy) [
      • Organization for Economic Cooperation and Development
      Fertility rates (indicator).
      ].
      Infertility is a global public health problem, and the proportion of infertile couples worldwide is increasing [

      World Health Organization. Health topics: infertility [Internet]. Geneva: World Health Organization; [cited 2022 May 9]. Available from: https://www.who.int/health-topics/infertility#tab=tab_1.

      ]. Infertility can easily act as a chronic stressor [
      • Lee Y.S.
      • Choi S.M.
      • Kwon J.H.
      Psychosocial predictors of infertility distress in women.
      ] and is a low-control stressor [
      • Maroufizadeh S.
      • Foroudifard F.
      • Navid B.
      • Ezabadi Z.
      • Sobati B.
      • Omani-Samani R.
      The Perceived Stress Scale (PSS-10) in women experiencing infertility: a reliability and validity study.
      ]; even if the cause of infertility is in men, women are more affected than men [
      • Taghipour A.
      • Karimi F.Z.
      • Roudsari R.L.
      • Mazlom S.R.
      Coping strategies of women following the diagnosis of infertility in their spouses: a qualitative study.
      ]. Recently, infertility has been increasing due to frequent miscarriages, age, long-term use of contraceptives, social stress, changes in eating habits and lifestyle, increases in women's social activities, and delays in marriage [

      Centers for Disease Control and Prevention. Reproductive health: infertility [Internet]. Atlanta: Centers for Disease Control and Prevention [cited 2022 May 9]. Available from: http://www.cdc.gov/reproductivehealth/infertility/index.htm#:∼:text=What%20is%20 infertility%3F,6%20months%20of%20unprotected%20sex.

      ]. Therefore, in situations where the number of infertile women is increasing and various health problems caused by infertility are related [
      • Inhorn M.C.
      • Patrizio P.
      Infertility around the globe: new thinking on gender, reproductive technologies and global movements in the 21st century.
      ], it is necessary to investigate the factors related to the QoL of infertile women.
      The QoL of infertile women is generally low [
      • Yang S.R.
      • Yeo J.H.
      Effects of irrational parenthood cognition, post traumatic stress disorder and spousal support on QoL of infertile women.
      ]. According to previous research, infertile Italian women perceive QoL as very low [
      • Zurlo M.C.
      • Cattaneo Della Volta M.F.
      • Vallone F.
      Predictors of QoL and psychological health in infertile couples: moderating role of the duration of infertility.
      ], and infertile women in China also report lower QoL [
      • Li Y.
      • Zhang X.
      • Shi M.
      • Guo S.
      • Wang L.
      Resilience moderates the relationship between infertility-related stress and fertility QoL in women with infertility: a cross-sectional study.
      ]. Compared with women of childbearing age, infertile women experience lower QoL [
      • Aduloju O.P.
      • Olaogun O.D.
      • Aduloju T.
      Quality of life in women of reproductive age: a comparative study of infertile and fertile women in a Nigerian tertiary center.
      ]. Moreover, women undergoing in vitro fertilization (IVF) for infertility have a lower QoL than other women of childbearing age [
      • Masoumi S.Z.
      • Garousian M.
      • Khani S.
      • Oliaei S.R.
      • Shayan A.
      Comparison of quality of life, sexual satisfaction and marital satisfaction between fertile and infertile couples.
      ,
      • Massarotti C.
      • Gentile G.
      • Ferreccio C.
      • Scaruffi P.
      • Remorgida V.
      • Anserini P.
      Impact of infertility and infertility treatments on QoL and levels of anxiety and depression in women undergoing in vitro fertilization.
      ], which affects not only infertile women but also the QoL of their spouse [
      • Casu G.
      • Ulivi G.
      • Zaia V.
      • Fernandes Martins M.D.C.
      • Parente Barbosa C.
      • Gremigni P.
      Spirituality, infertility-related stress, and QoL in Brazilian infertile couples: analysis using the actor-partner interdependence mediation model.
      ].
      Various factors have been reported to affect the QoL of infertile women. Infertile women experience various physical, psychological, and relational problems that affect their QoL [
      • Kim Y.M.
      • Nho J.H.
      Factors influencing infertility-related QoL in women with infertility.
      ]. Among these are demographic factors such as the duration of marriage and burden of the cost of infertility testing, burden of infertility, age [
      • Lee H.S.
      • Boo S.
      • Ahn J.A.
      • Song J.E.
      Effects of uncertainty and spousal support on infertility-related quality of life in women undergoing assisted reproductive technologies.
      ], education level, duration of infertility treatment [
      • Namavar Jahromi B.
      • Mansouri M.
      • Forouhari S.
      • Poordast T.
      • Salehi A.
      Quality of life and its influencing factors of couples referred to an infertility center in Shiraz, Iran.
      ], relationship with spouse [
      • Yang S.R.
      • Yeo J.H.
      Effects of irrational parenthood cognition, post traumatic stress disorder and spousal support on QoL of infertile women.
      ,
      • Jung Y.J.
      • Kim H.Y.
      Factors influencing infertility-related quality of life in women undergoing assisted reproductive techniques: focusing on depression and resilience.
      ], physical factors such as fatigue [
      • Kim Y.M.
      • Nho J.H.
      Factors influencing infertility-related QoL in women with infertility.
      ,
      • Kim M.
      • Moon S.H.
      • Kim J.E.
      Effects of psychological intervention for Korean infertile women under in Vitro Fertilization on infertility stress, depression, intimacy, sexual satisfaction and fatigue.
      ], psychological factors such as stress [
      • Yang S.R.
      • Yeo J.H.
      Effects of irrational parenthood cognition, post traumatic stress disorder and spousal support on QoL of infertile women.
      ], uncertainty [
      • Lee H.S.
      • Boo S.
      • Ahn J.A.
      • Song J.E.
      Effects of uncertainty and spousal support on infertility-related quality of life in women undergoing assisted reproductive technologies.
      ], depression [
      • Kim Y.M.
      • Nho J.H.
      Factors influencing infertility-related QoL in women with infertility.
      ,
      • Tola E.N.
      • Eris Yalcin S.
      • Dugan N.
      • Oral B.
      The association of type D personality and depression with infertility in women.
      ], and type-D personality [
      • Tola E.N.
      • Eris Yalcin S.
      • Dugan N.
      • Oral B.
      The association of type D personality and depression with infertility in women.
      ].
      Fatigue is a symptom of physical problems that occur when attempting to conceive through fertility procedures [
      • Kim Y.M.
      • Nho J.H.
      Factors influencing infertility-related QoL in women with infertility.
      ]. In a study of 140 infertile women, approximately 37% complained of fatigue, and the higher the fatigue of infertile women, the lower the QoL [
      • Kim Y.M.
      • Nho J.H.
      Factors influencing infertility-related QoL in women with infertility.
      ].
      Type-D personality refers to a personality that is vulnerable to negative emotions, such as depression, anxiety, and stress, and tends to consciously suppress self-expression in social interactions [
      • Denollet J.
      Type D personality. A potential risk factor refined.
      ,
      • Denollet J.
      DS14: standard assessment of negative affectivity, social inhibition, and Type D personality.
      ]. Negative affectivity refers to a persistent negative emotional state regardless of time and place, and social inhibition means suppressing the expression of emotions and behaviors to avoid the potential fear of being rejected in social relationships with others [
      • Denollet J.
      Type D personality. A potential risk factor refined.
      ,
      • Denollet J.
      DS14: standard assessment of negative affectivity, social inhibition, and Type D personality.
      ]. According to previous studies, people with a type-D personality are more likely to experience lower QoL than people with a non-type-D personality [
      • Mols F.
      • Denollet J.
      Type D personality in the general population: a systematic review of health status, mechanisms of disease, and work-related problems.
      ]. According to a study on infertile women with type-D personality, depression and type-D personality were higher in the infertility group, and type-D personality had a significant correlation with infertility. In particular, it was confirmed that there was a negative correlation with young infertile women (<35 years old) [
      • Tola E.N.
      • Eris Yalcin S.
      • Dugan N.
      • Oral B.
      The association of type D personality and depression with infertility in women.
      ]; therefore, it is necessary to investigate the QoL of infertile women according to their type-D personality.
      Despite social changes, in which the number of subjects diagnosed with infertility is increasing, research so far has been limited to the fragmentary evaluation of each variable, and considering the classification according to the type-D personality of infertile women, it is difficult to find studies that affect QoL according to type-D personality. Therefore, researchers have identified factors affecting QoL in infertile women and investigated the correlation between fatigue and QoL according to the type-D personality. The specific purposes were as follows: i) to identify general characteristics, fatigue, and QoL related to infertility according to type-D personality of infertile women, ii) investigate QoL according to participant characteristics, iii) investigate the correlation between variables, and iv) identify factors affecting infertility-related QoL in infertile women.

      Methods

      Design

      This study used a descriptive correlational research design to identify factors affecting fertility-related QoL in infertile women through a cross-sectional survey.

      Setting and study participants

      The present study was conducted on 150 infertile women who did not have children naturally, even after more than one year of marriage. All women with infertility problems, including primary and secondary infertility, were targeted, and the specific criteria were as follows. In the present study, convenience was extracted from women who were diagnosed with infertility at a fertility hospital located in the J province. As for the sample size, multiple regression analysis with a significance level of .05, power of .8, and effect size of .15 median based on a previous study [
      • Aarts J.W.
      • Huppelschoten A.G.
      • van Empel I.W.
      • Boivin J.
      • Verhaak C.M.
      • Kremer J.A.
      • et al.
      How patient-centered care relates to patients' quality of life and distress: a study in 427 women experiencing infertility.
      ], was performed using G∗Power 3.1.9.7 (Universität Düsseldorf, Düsseldorf, Germany). When 11 predictors (women' age, spouse's age, religion, occupation, education level, monthly income, duration of infertility treatment, experienced infertility treatment methods, relationship with the spouse, fatigue, type-D personality) were input, 123 was the minimum sample size. A total of 150 questionnaires were distributed and collected considering the omission of responses. After excluding one questionnaire owing to insincere responses and errors in filling out, 149 subjects participated in the study (response rate: 99.3%). Data were collected from October 30, 2020, to January 8, 2021. Data were collected from two obstetrics and gynecology clinics and two public health centers. After obtaining permission from the heads of the institutions, a poster was attached to the centers to guide the recruitment of research participants. After obtaining voluntary consent, participants filled out the self-administered questionnaires in offices at centers with quiet, comfortable, and private places. The questionnaire took approximately 20 minutes and was sealed and collected thereafter. The inclusion criteria were as follows: i) infertile women older than 19 years and ii) diagnosed with infertility at a hospital. The exclusion criteria were as follows: i) those with diseases other than infertility, and ii) those who had been diagnosed with depression or had a disease that may affect fatigue.

      Ethical considerations

      This study was approved by the Institutional Review Board of Jeonbuk National University (no. 2020-08-008-001). In accordance with the Helsinki Declaration, voluntary written consent was obtained after explaining the privacy guarantee, research content, purpose, anonymity, and possibility of opting out.

      Measures

      Type-D personality

      The type-D personality measured by the type-D scale-14 (DS14) [
      • Denollet J.
      DS14: standard assessment of negative affectivity, social inhibition, and Type D personality.
      ] consists of seven items each for the “negative affectivity” (NA) and “social inhibition” (SI) domains. Each item is measured on a five-point Likert scale and composed of 0–4 points. The NA and SI scales range from 0 to 28 points, respectively. The cutoff on both subdomains is 10 points; a score of 10 or more in each domain is classified as a type-D personality (i.e., NA ≥ 10 and SI ≥ 10), and others are classified as non-type-D personality [
      • Denollet J.
      DS14: standard assessment of negative affectivity, social inhibition, and Type D personality.
      ]. The Cronbach's α of original version of the DS 14 was .88 for the NA and .82 for the SI [
      • Denollet J.
      DS14: standard assessment of negative affectivity, social inhibition, and Type D personality.
      ], and the those of Korean version was .88 for the NA and .86 for the SI [
      • Lim H.E.
      • Lee M.S.
      • Ko Y.H.
      • Park Y.M.
      • Joe S.H.
      • Kim Y.K.
      • et al.
      Assessment of the type D personality construct in the Korean population: a validation study of the Korean DS14.
      ]. In this study, Cronbach's α was .87 for the NA and .85 for the SI. It was used after receiving approval from the copyright holder (Copyright Clearance Center) of original version [
      • Denollet J.
      DS14: standard assessment of negative affectivity, social inhibition, and Type D personality.
      ] and translator's Korean version.

      Fatigue

      The fatigue was measured The Fatigue Severity Scale (FSS) [
      • Krupp L.B.
      • LaRocca N.G.
      • Muir-Nash J.
      • Steinberg A.D.
      The fatigue severity scale. Application to patients with multiple sclerosis and systemic lupus erythematosus.
      ] The FSS consists of a total of nine questions, “not at all” 1 to “strongly agree” 7 points. The total score was calculated as the average of the scores for each item and ranged from 1 to 7, with a higher average value indicating more severe fatigue. If the average score was 4 or higher, it was interpreted as the fatigue group, and if it was less than 4, it was classified as the non-fatigue group. Cronbach's α of the original version of the FSS was .89 [
      • Krupp L.B.
      • LaRocca N.G.
      • Muir-Nash J.
      • Steinberg A.D.
      The fatigue severity scale. Application to patients with multiple sclerosis and systemic lupus erythematosus.
      ] and that of the Korean version of the FSS was .94 [
      • Chung K.I.
      • Song C.H.
      Clinical usefulness of fatigue severity scale for patients with fatigue, anxiety, or depression.
      ]. In this study, the Cronbach's α was .91. It was used after the receiving approval from the translator's Korean version and ⓒ1985 Lauren B. Krupp. reproduced with permission from the author.

      Quality of life

      The Fertility QoL tool (FertiQoL) was used to measure the QoL of infertile women [
      • Boivin J.
      • Takefman J.
      • Braverman A.
      The Fertility quality of life (FertiQoL) tool: development and general psychometric properties.
      ]. This scale was developed to measure the QoL of people with infertility problems, as presented by Boivin and Schmidt in collaboration with the European Association for Reproductive Embryology and the American Society of Reproductive Medicine [
      • Boivin J.
      • Takefman J.
      • Braverman A.
      The Fertility quality of life (FertiQoL) tool: development and general psychometric properties.
      ]. The Korean version of the FertiQoL, translated into 45 languages, was used, and its validity was confirmed in Korean infertile women [
      • Chi H.J.
      • Park I.H.
      • Sun H.G.
      • Kim J.W.
      • Lee K.H.
      Psychological distress and fertility quality of life (FertiQoL) in infertile Korean women: the first validation study of Korean FertiQoL.
      ]. It has 34 items, and the higher the total score, the higher the QoL related to infertility. The Cronbach's α of the original version of the FertiQoL was .92 [
      • Boivin J.
      • Takefman J.
      • Braverman A.
      The Fertility quality of life (FertiQoL) tool: development and general psychometric properties.
      ]. In this study, the Cronbach's α was .92.

      General characteristics

      General factors such as age (women with infertility, spouse), religion, occupation, education level, average monthly income, and fertility-related characteristics, including the duration of infertility treatment, experience of infertility treatment methods, and relationship with the spouse during infertility treatment.

      Statistical analysis

      The collected data were statistically analyzed using SPSS (version 25.0; IBM SPSS Statistics for Windows, IBM Corp., Armonk, NY, USA). An independent t-test and chi-square test were conducted to compare the differences in infertility-related QoL according to participants' demographic characteristics. Pearson's correlation analysis was performed to investigate the correlation between age, fatigue, and QoL. Hierarchical multiple regression analysis was used to identify the factors affecting the QoL of infertile women according to their type-D personality.

      Results

      General characteristics, fatigue, and QoL according to type-D personality

      The mean age of the participants and spouses was 35.61 ± 4.62 years (range 25-46) and 37.57 ± 5.00 years (range 27–55), respectively. Of those who had undergone infertility treatment for >36 months, 22.8%. Among the participants, 40.9% belonged to the type-D personality group. Participants with and without type-D personality showed significant differences in their relationship with their spouses (χ2 = 4.44, p = .035) (Table 1). The group with type-D personality had significantly higher fatigue than the group with non-type-D personality (t = 17.38, p < .001), including prevalence of fatigue (χ2 = 12.75, p < .001). In addition, the group with type-D personality had significantly lower QoL than the group with non-type-D personality (t = 16.71, p < .001) in all QoL subscales except for overall physical health and environment (Table 1 and Figure 1).
      Table 1General Characteristics of the Type-D and Non-Type-D Personality Groups (N = 149).
      VariablesCategoriesTotal (n = 149)Type-D (n = 61)Non-type-D (n = 88)t or χ2 or FpRange
      M ± SD, n (%)
      Demographic characteristics
      Age (year)Women35.61 ± 4.6235.75 ± 4.2635.51 ± 4.88.31.75425–46
      <3564 (43.0)22 (36.1)42 (47.7)2.00.180
      ≥3585 (57.0)39 (63.9)46 (52.3)
      Husband37.57 ± 5.0037.49 ± 4.9937.63 ± 5.04−.16.87427–55
      <3543 (28.9)18 (29.5)25 (28.4).02.884
      ≥35106 (71.1)43 (70.5)63 (71.6)
      ReligionYes75 (50.3)30 (49.2)45 (51.1).06.868
      No74 (49.7)31 (50.8)43 (48.9)
      OccupationYes95 (63.8)41 (43.2)54 (56.8).53.465
      No54 (36.2)20 (37.0)34 (63.0)
      Education≤High school29 (19.5)9 (14.8)20 (22.7)1.46.294
      ≥University120 (80.5)52 (85.2)68 (77.3)
      Monthly income (thousand won)<3,00045 (30.2)18 (29.5)27 (30.7)2.92.231
      3,000–4,00049 (32.9)16 (26.2)33 (37.5)
      ≥4,00055 (36.9)27 (44.3)28 (31.8)
      Fertility-related characteristics
      Duration of infertility treatment (in months)24.24 ± 18.6129.26 ± 21.2020.76 ± 15.78−2.66.009
      <36115 (77.2)42 (68.9)73 (83.0)4.07.044
      ≥3634 (22.8)19 (31.1)15 (17.0)
      Experienced treatment (double choice)OI (yes)88 (59.1)40 (65.6)48 (54.5)1.81.178
       (no)61 (40.9)21 (34.4)40 (45.5)
      IUI (yes)74 (49.7)32 (52.5)42 (47.7).32.570
       (no)75 (50.3)29 (47.5)46 (52.3)
      IVF (yes)81 (54.4)35 (57.4)46 (52.3).38.538
       (no)68 (45.6)26 (42.6)42 (47.7)
      Others (yes)16 (10.7)5 (8.2)11 (12.5).70.404
       (no)133 (89.3)56 (91.8)77 (87.5)
      Relationship with spouseGood128 (85.9)48 (78.7)80 (90.9)4.44.035
      Bad21 (14.1)13 (21.3)8 (9.1)
      FatigueTotal3.48 ± 1.243.97 ± .973.13 ± 1.294.52<.001
      ANCOVA adjusted relationship with spouse.
      1.11–6.11
      Yes (≥4)51 (34.2)31 (50.8)20 (22.7)12.63<.001
      No (<4)98 (65.8)30 (49.2)68 (77.3)
      Fertility-related

      Quality of Life
      Total58.98 ± 11.9954.46 ± 12.9362.11 ± 10.25−3.86<.001
      ANCOVA adjusted relationship with spouse.
      28.65–88.02
      Overall physical health2.27 ± .712.21 ± .762.31 ± .68−.79.432
      ANCOVA adjusted relationship with spouse.
      1–4
      QoL Life satisfaction2.50 ± .712.28 ± .662.66 ± .71−3.31.001
      ANCOVA adjusted relationship with spouse.
      0–4
      Core Ferti QoL62.86 ± 14.9457.55 ± 16.3966.55 ± 12.69−3.61<.001
      ANCOVA adjusted relationship with spouse.
      21.88–92.71
      Emotional61.86 ± 18.3756.15 ± 21.0665.81 ± 15.14−3.08.003
      ANCOVA adjusted relationship with spouse.
      12.50–100.0
      Mind-body61.88 ± 19.1957.04 ± 19.8065.25 ± 18.11−2.62.010
      ANCOVA adjusted relationship with spouse.
      12.67–100.0
      Relational65.41 ± 17.0659.77 ± 17.4969.32 ± 15.69−3.48.001
      ANCOVA adjusted relationship with spouse.
      20.83–100.0
      Social62.30 ± 16.6557.24 ± 17.6465.81 ± 15.05−3.19.002
      ANCOVA adjusted relationship with spouse.
      12.50–95.83
      Treatment Ferti QoL55.09 ± 11.5651.37 ± 11.6357.67 ± 10.85−3.39.001
      ANCOVA adjusted relationship with spouse.
      30.21–85.42
      Environment51.96 ± 11.9649.45 ± 12.2153.69 ± 11.54−2.15.033
      ANCOVA adjusted relationship with spouse.
      25.00–87.50
      Tolerability58.22 ± 18.4753.28 ± 18.9961.65 ± 17.40−2.78.006
      ANCOVA adjusted relationship with spouse.
      18.75–100.0
      Note, IUI = intrauterine insemination; IVF = in vitro fertilization; OI = ovulation induction.
      a ANCOVA adjusted relationship with spouse.
      Figure 1
      Figure 1Fatigue and Quality of Life according to Type-D Personality.

      QoL according to general characteristics

      Women who had undergone over 36 months' duration of infertility treatment (t = 4.20, p < .001) and had a good relationship with their spouse (t = 2.90, p = .004) had higher QoL scores than those with less than 36 months' duration of infertility treatment and poor relationship with spouse (Table 2).
      Table 2Quality of Life According to General Characteristics (N = 149).
      VariablesCategoriesQuality of lifet or Fp
      M ± SD
      Women's age (in years)<3559.37 ± 9.95.36.721
      ≥3558.68 ± 13.38
      Husband's age (in years)<3558.36 ± 11.64−.41.523
      ≥3559.23 ± 12.18
      ReligionYes57.83 ± 10.34−1.17.244
      No60.14 ± 13.43
      OccupationYes58.99 ± 12.44.01.990
      No58.96 ± 11.28
      Education≤High school60.52 ± 12.59.77.440
      ≥University58.60 ± 11.87
      Monthly income (thousand won)<3,00058.60 ± 11.02.37.690
      3,000–4,00060.17 ± 10.92
      ≥4,00058.22 ± 13.69
      Duration of infertility treatment (month)<3661.11 ± 10.914.20<.001
      ≥3651.78 ± 12.84
      Experienced treatment (double choice)OIYes57.64 ± 12.50−1.64.103
      No60.90 ± 11.04
      IUIYes57.24 ± 12.54−1.77.080
      No60.69 ± 11.25
      IVFYes57.36 ± 13.53−1.86.065
      No60.90 ± 9.61
      OthersYes62.21 ± 11.911.14.255
      No58.59 ± 11.99
      Relationship with spouseGood60.10 ± 11.532.90.004
      Bad52.11 ± 12.73
      Note, IUI = intrauterine insemination; IVF = in vitro fertilization; OI = Ovulation induction.

      Correlation between variables in infertile women

      Fatigue in infertile women was negatively correlated with QoL (r = −.35, p < .001). Women's age showed a positive correlation with husband's age (r = .69, p < .001) (Table 3).
      Table 3Correlation of Fatigue and Quality of Life (N = 149).
      VariablesWomen's ageHusband's ageFatigue
      r (p)r (p)r (p)
      Husband's age.69 (<.001)
      Fatigue−.01 (.920)−.04 (.620)
      QoL.04 (.658).02 (.806)−.35 (<.001)
      Note, QoL = quality of life.

      Factors affecting QoL in infertile women

      A hierarchical regression analysis was performed to investigate the factors that affected QoL in women who were infertile. Based on previous studies [
      • Hwang S.L.
      • Liao W.C.
      • Huang T.Y.
      Predictors of quality of life in patients with heart failure.
      ,
      • Williams L.
      • O'Connor R.C.
      • Grubb N.
      • O'Carroll R.
      Type D personality predicts poor medication adherence in myocardial infarction patients.
      ,
      • Son Y.J.
      • Song E.K.
      The impact of Type D personality and high-sensitivity C-reactive protein on health-related quality of life in patients with artrial fibrillation.
      ], the main variables entered were general characteristics that showed differences in QoL (duration of infertility treatment and relationship with spouse) in the first model and fatigue and type-D personality as physical and psychological factors in the second model, respectively. To confirm the assumption of linear regression, the linearity of all variables and normality were examined. The Durbin–Watson value was close to 2 (1.87), which indicated no problem of autocorrelation. The tolerance ranged from .86 to .97, which was greater than .10, and the variation inflation factor showed that values of all variables were not greater than 10 (1.03 to 1.16), which indicated no issue of multicollinearity. The residual histogram and residual normal probability and homoscedasticity graphs were examined to confirm the normality of residuals. The results were deemed satisfactory. Cook's distance was less than 1.0, at .00 to .06, which implied that no cases needed to be deleted.
      In model 1, duration of infertility treatment [>36 months] (β = −.29, p < .001) and relationship with spouse [bad] (β = −.22, p = .006) were demonstrated to be statistically significant. This model was statistically significant (F = 11.75, p < .001) and explained 13.0% of the variance in QoL in infertile women. In model 2, fatigue and type-D personality were added to the regression model, and type-D personality was treated as a dummy variable. Fatigue (β = −.23, p = .003) was the most significant factor, followed by duration of infertility treatment [>36 months] (β = −.22, p = .003), type-D personality [yes] (β = −.18, p = .025), and relationship with spouse [bad] (β = −.17, p = .024). Model 2 was also statistically significant (F = 11.64, p < .001), and the explanatory power of model 2 was 22.0%, an increase of 9% from model 1 (Table 4).
      Table 4Factors Affecting Quality of Life in Infertility Women (N = 149).
      Variable (constant)Step 1Step 2
      BSEβtpBSEβtp
      62.381.1653.80<.00171.192.5927.45<.001
      Duration of infertility treatmenta−7.491.98−.29−3.78<.001−5.711.91−.22−2.99.003
      Relationship with spouseb−7.422.64−.22−2.81.006−5.772.53−.17−2.28.024
      Fatigue−2.25.75−.23−2.99.003
      Type-D personalityc−4.301.90−.18−2.27.025
      Adjusted R2.13.22
      Adjusted R2 change.13.09
      F11.7511.64
      F change11.7510.07
      p<.001<.001
      Note, Dummy variable references aDuration of infertility treatment (≤36 month), bRelationship with spouse (good), cType-D personality (no).
      Durbin–Watson 1.87; tolerance: .86–.97; variable inflation factors: 1.03–1.16.

      Discussion

      This study attempted to identify the factors affecting the QoL of infertile women and discuss the factors that have the greatest influence on QoL. The duration of treatment among the general characteristics had the greatest influence on the QoL. Fatigue had the greatest influence on the QoL of infertile women in this study. Infertility treatment causes physical and psychological fatigue during examinations [
      • Tola E.N.
      • Eris Yalcin S.
      • Dugan N.
      • Oral B.
      The association of type D personality and depression with infertility in women.
      ]. Physical fatigue due to frequent hospital visits and invasive procedures (ovulation induction, intrauterine insemination, and in vitro fertilization) can cause anxiety and tension, making it difficult to treat infertility [
      • Kim M.O.
      • Hong J.E.
      • Lee E.Y.
      The relationship between fatigue, health-promoting behavior, and depression among infertile women.
      ]. Therefore, considering that the fatigue of infertile women may be aggravated after the failure of the infertility treatment procedure, it is necessary for healthcare providers to understand the patient through information regarding their individual coping style checked in advance and induce them to use the active coping style and music therapy to reduce fatigue during treatment [
      • Nho Y.H.
      Development of an imagery-focused music listening program to improve emotion regulation among infertile women.
      ]; Therefore, various active nursing interventions or strategies are needed to reduce the fatigue of infertile women and improve their QoL in the future.
      The second factor was the duration of treatment among the general characteristics. QoL was found to be low when the infertility treatment period was long, which was similar to the results of previous studies [
      • Lee Y.H.
      • Park J.S.
      Factors affecting infertility-related QoL among infertility women.
      ]. Thus, to improve the QoL related to infertility, an educational program can help infertile women recognize infertility early and actively treat it through education or promotion as a policy for infertile women.
      The third factor influencing QoL was type-D personality. The type-D personality of infertile women also affects QoL. In this study, 40.9% of the participants had a type-D personality; 22.4% to 36.2% of foreign university students [
      • Mols F.
      • Denollet J.
      Type D personality in the general population: a systematic review of health status, mechanisms of disease, and work-related problems.
      ,
      • Škodová Z.
      • Bánovčinová L.
      Type D personality is a predictor of resilience among nursing students.
      ], 30.8% of college students in Korea [
      • Kim S.R.
      • Nho J.H.
      • Kim H.Y.
      Influence of Type D personality on QoL in university students: the mediating effect of health-promoting behavior and subjective health status.
      ], 34.5% of middle-aged women [
      • Bae S.H.
      • Park J.H.
      • Oh E.
      A comparison of the health status and health-promoting behaviors between type D personality and non-type D personality in middle-aged women.
      ], and 56% of ovarian cancer patients receiving chemotherapy [
      • Kim S.R.
      • Nho J.H.
      • Nam J.H.
      Relationships among Type D personality, symptoms, and QoL in patients with ovarian cancer receiving chemotherapy.
      ] had type-D personality. Considering that hemodialysis patients account for 42.9% of hemodialysis patients [
      • Kwon G.S.
      • Lim K.H.
      Mediating effects of depression and social support between Type D personality and QoL in hemodialysis patients.
      ], the type-D personality of infertile women is higher than that of general college students and middle-aged women, showing a similar aspect to the type-D prevalence of subjects with disease, indicating that active management of infertile women with type-D personality is urgently needed. Considering that the type-D personality is vulnerable to negative affectivity, people belonging to this group experience many negative emotions regardless of time and place and have a tendency to isolate themselves due to social inhibition [
      • Denollet J.
      DS14: standard assessment of negative affectivity, social inhibition, and Type D personality.
      ,
      • Staniute M.
      • Brozaitiene J.
      • Burkauskas J.
      • Kazukauskiene N.
      • Mickuviene N.
      • Bunevicius R.
      Type D personality, mental distress, social support and health-related quality of life in coronary artery disease patients with heart failure: a longitudinal observational study.
      ]. It is thought that the special situation of infertile women and the phenomenon of infertility treatment increase their negative affectivity and social inhibition. One reason for this improvement is that infertile women express their feelings and negative emotions to those close to them, such as their spouses and family [
      • Luk B.H.K.
      • Loke A.Y.
      Sexual satisfaction, intimacy and relationship of couples undergoing infertility treatment.
      ]. It seems that interventions that allow people to express their emotions are necessary. As social inhibition intensifies social alienation, it is necessary to find ways to alleviate social inhibition and strengthen social belonging by encouraging not only infertile women, but also their spouses to participate in social activities such as infertility-related lectures and self-help groups. As lifestyle interventions, including physical activity and stress reduction, were effective in reducing type-D personality traits in middle-aged women [
      • Kim E.J.
      • Nho J.H.
      • Kim H.Y.
      • Park S.K.
      The effects of lifestyle interventions on the health-promoting behavior, type D personality, cognitive function and body composition of low-income middle-aged Korean women.
      ]. Further studies are needed to confirm the effect of applying a lifestyle intervention program for infertile women during the treatment process.
      In the present study, participants with type-D personality had higher fatigue and lower QoL than those in the non-type-D group. Type-D personality has a direct impact on QoL [
      • Kim S.R.
      • Nho J.H.
      • Kim H.Y.
      Influence of Type D personality on QoL in university students: the mediating effect of health-promoting behavior and subjective health status.
      ], and people with type-D personality have been reported to have a lower QoL [
      • Kessing D.
      • Denollet J.
      • Widdershoven J.
      • Kupper N.
      Self-care and health-related QoL in chronic heart failure: a longitudinal analysis.
      ]. These personality traits are said to have a significant correlation with infertility. Therefore, there is a need for interest in and support for the QoL of infertile women with this type-D personality, and efforts are needed to actively cope with infertility problems, such as developing interventions including education, music therapy, lifestyle intervention, spousal cooperation, and active management to improve the type-D personality and QoL of infertile women. In this study, the type-D personality group had a negative relationship with the spouse. These results suggest that social isolation may have a relationship with one's spouse. Therefore, it is necessary to assess the type-D personality of women with infertility because those with a type-D personality have a worse relationship with their spouse.
      The fourth factor was the relationship with the spouse, which influenced the QoL of infertile women. When the relationship with the spouse was poor, QoL related to infertility in infertile women was low. This is in line with a study [
      • Kim Y.M.
      • Nho J.H.
      Factors influencing infertility-related QoL in women with infertility.
      ] that shows that the spouse's attitude has an effect on QoL, and that QoL is higher when the spouse's attitude is active than when it is passive. Therefore, during the infertility treatment period, spouses' active cooperation with the treatment and support for infertile women is necessary. Infertility is not solely a woman's problem—couples must face it together, as there are limits to individual coping strategies [
      • Lee Y.S.
      • Choi S.M.
      • Kwon J.H.
      Psychosocial predictors of infertility distress in women.
      ]. Thus, it is necessary to develop and apply nursing education and related programs for infertile couples who value relationships with their spouses during infertility treatment.
      This study had some limitations. First, there are various infertility treatment methods experienced by women, which may lead to differences in fatigue and QoL. Second, this study used a cross-sectional design; thus, we did not demonstrate the longitudinal impact of type-D personality on QoL. Nevertheless, this study identified the influence of fatigue, type-D personality, and demographic characteristics on QoL in infertile women.

      Conclusion

      The present study is significant as it is the first to be conducted in South Korea on infertile women according to type-D personality type. To improve the QoL of infertile women, it is necessary to develop and apply various nursing interventions such as education, lifestyle interventions, music therapy, and stress management programs in which the spouse participates in consideration of the infertility treatment period.

      Funding

      This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (No. NRF-2020R1F1A1050767 ).

      Authorship

      All authors listed meet the authorship criteria according to the latest guidelines of the international Committee of Medical Journal Editors, and all authors are in agreement with the article.

      Conflicts of interest

      The authors declare no potential conflicts of interest with respect to the research, authorship, or publication of this article.

      Data availability statement

      The data that support the findings of this study are available on request from the corresponding author.

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