Introduction

It is generally accepted that sexual health is one of the major factors affecting the sustainability of marital life. Desirable sexual function can be considered among the most significant elements determining couples' happiness (1). Sexual function is a real physiological-psychological experience that engages both brain and body. Sexual activity is also a pleasing bilateral communication to get rid of emotional and physical stress. The
sexual function cycle consists of libido, sexual stimulation, sexual satisfaction, and orgasm (2).

Lack of attention to sexual function can cause persistent and profound disorders in couples' relationship. Any unpleasant difference in this relationship leads to the feelings of deprivation, jealousy, suspicion, anxiety, quarrel-picking, blaming the other side for life problems, humiliation, exaggeration of problems, and hatred of the partner. The emergence of these feelings would ultimately result in a cold and spiritless life or marital life breakdown. This factor is the cause of 60-70% of divorces on average (3).

The rates of sexual function vary among women. For example, Leiblum et al. (2003) claimed that 25-63% of women suffered from such a dysfunction (4); however, Dobkin et al. (2006) reported this rate to be 25% (5). Mohammadi et al. (2008) found that 83% of the Iranian women had sexual dysfunction (6). In general, sexual behaviors are not identical in different individuals (7). It seems that an individuals’ personality traits, interpersonal relationships, family conditions, social and cultural conditions, environment, background of sexual affairs, physical and mental health, temperament, and hormonal status affect his/her sexual function (8).

The term “temperament” literally means intermingling (9). In the Iranian traditional medicine, there are nine types of temperaments (i.e., cold, hot, moist, and dry known as singular temperament, as well as cold-moist, cold-dry, hot-moist, and hot-dry called compound temperaments, and finally moderate). There is no human being with a truly moderate temperament, and one of such temperaments is more or less dominant in each individual.

Accordingly, a fully moderate or singular temperament with a balanced mixture of two temperaments is rare (10). Among the factors determining the temperament, the hot and cold temperaments have been concerned and used more often as compared to the secondary ones. Accordingly, all individuals can generally be classified into two cold (i.e., cold, cold-moist, and cold-dry) and hot (i.e., hot, hot-moist, and hot-dry) groups (9).

The deficiency of temperament balance is one of the main causes of various diseases. According to the traditional medicine, the balance of these four tempers determines an individual’s temperament. The dominance of each temper can determine the physical, psychological, and emotional attributes of a person (11). In a study performed by Mortazavi et al. (2013), marital conflicts were reported to increase with the enhancement of sexual frigidity (12).

In the same vein, McCup (1997) concluded that couples with more marital conflicts reported higher sexual dysfunction (13). However, to the best of our knowledge, no research has investigated sexual function with respect to different temperaments. Regarding this, the present study was performed to determine the relationship of hot and cold temperaments with sexual function among the women of reproductive age.

Materials and Methods

This descriptive-correlational study was conducted on 200 women within the age range of 20-40 years referring to five health centers in Mashhad, Iran, to receive maternity and child health services, vaccination, and family planning counseling in 2017. This study was approved by the Ethics Committee of Mashhad University of Medical Sciences, Mashhad, Iran. After obtaining a written introduction letter from the Faculty of Nursing and Midwifery of Mashhad University and making necessary coordination with the authorities of the concerned health centers, the researchers performed sampling using the convenience sampling technique.

Given the lack of similar articles on the relationship between sexual function and temperament, the sample size was estimated as 100 cases at the confidence intervals of 99% and 90% based on a study performed by Mortazavi et al. (2013). Regarding the issue under investigation and the possibility of further discussions about the temperament subcategories, 200 participants were included in the study.

The inclusion criteria were: 1) involvement in the first marital life, 2) having a sexual partner, 3) inhabitation in the same place with the husband, 4) no sexual dysfunction in husband, 5) no pregnancy, lactation, or intention to become pregnant, 6) a minimum interval of three months from child delivery, 7) non-consumption of traditional medicine to promote sexual function, 8) diagnosis of no medical illness in couples, 9) lack of mental illnesses, 10) non-use of mental health medications by couples, 11) no severe stressful incidents during the study, 12) lack of vaginal infections, 13) non-use of vaginal creams, and 14) willingness to participate in the study. On the other hand, the participants with sexual distress, moderate temperament, or stress, depressions, and anxiety scores greater than or equal to 25, 20, and 14, respectively, were excluded from the study.

After receiving the participants’ written informed consent and ensuring them about the data confidentiality, the participants completed the questionnaires individually in the presence of the researchers. The data collection instruments included a demographic form, a temperament questionnaire, 21-Item Depression, Anxiety,
and Stress Scale (DASS-21), Female Sexual Function Index (FSFI), and Female Sexual Distress Scale (FSDS).

Demographic form contained 8 items regarding personal attributes, the effects of which were measured in this study. These variables included age, age of the last child, age of marriage, duration of marriage, gravidity, number of children, type of child delivery, and frequency of sexual intercourse per month.

Temperament questionnaire consists of 10 items, the first 8 items of which facilitate the determination of the hot or cold temperament, and the last two assess the moist and dry temperaments. Each item was rated on a Likert scale (14). In this study, only the first eight items were employed, and individuals with moderate temperament were excluded from the study. In this instrument, the scores of ≤ 14 and 19 ≤ for the first eight items represent having cold and hot temperaments, respectively.

The validity of this questionnaire was confirmed by Mojahedi et al. in 2013 (14). Furthermore, the reliability of this tool was estimated as 82% using the test-retest method and Spearman-Brown correlation coefficient by Jafarinejad et al. (2015) (15). In the present study, the content validity of the questionnaire was also confirmed. The reliability of this instrument was also measured by means of test-retest method. To this end, ten participants completed the questionnaire with a 10-day interval, rendering a Spearman-Brown correlation coefficient of 0.92.

The Female Sexual Function Index, developed by Rosen et al. (2000), contains 19 items in 6 subscales, including libido, sexual stimulation, vaginal moisture, orgasm, pain during intercourse, and sexual satisfaction. The items in the libido and sexual satisfaction subscales are rated on a 5-point Likert scale (ranging within 1-5), and the other items on sexual stimulation, vaginal moisture, orgasm, and pain during intercourse were scored on a 6-point Likert scale (ranging within 0-5).

Score 0 indicates that the person has had no sexual intercourse during the past four weeks. In order to obtain the total score of the questionnaire, each subscale is multiplied by certain numerical coefficients (i.e., 0.6 for libido, 0.3 for sexual stimulation, vaginal moisture, and orgasms, and 0.4 for sexual satisfaction and sexual pain).

The libido subscale has a score range of 1.2-6, and the vaginal moisture, orgasm, sexual satisfaction, and sexual pain range within 0-6 with greater scores indicating lower amount of pain. The total scale had the minimum and maximum scores of 2 and 36, respectively (16). The validity of the Farsi version of this instrument in Iran was confirmed by Mohammadi in 2008 (17).

In the current study, the validity of this questionnaire confirmed using the content validity. The reliability of this tool was also approved by Mohammadi using internal consistency method and Cronbach's alpha coefficient, reporting a Cronbach's alpha coefficient of > 0.70 for the total scale and its subscales (17). In the present study, the reliability of this index was estimated as 0.89 using internal consistency method and Cronbach's alpha coefficient.

The FSDS entails three subscales, namely depression, anxiety, and stress, each of which included seven items. Each item is scored on a four-point Likert scale (ranging within 0-3). The final score of each subscale is obtained by summing up the scores of all items. The reliability of this scale was confirmed by Henry et al. (2005), reporting a Cronbach’s alpha coefficient of 0.82 (18). In the current study, Cronbach's Alpha coefficients were estimated as 0.7, 0.75, 0.85, and 0.87 for the depression, anxiety, and stress subscales, and the whole scale, respectively.

Female Sexual Distress Scale contains 12 items rated on a 5-point Likert scale ranging from 0 (i.e., never) to 4 (i.e., always). In this scale, scores greater than 15 are used as a cut-off point for sexual distress. This questionnaire was first developed by DeRogatis et al. (2002) to measure individual sex-related distress in women. Its reliability was first confirmed by DeRogatis et al. (2002) using a test-retest method with a one-week interval (r=0.76) (19). In this study, the reliability of this instrument was estimated as 0.93 using the internal consistency and Cronbach's alpha coefficient.

Firstly, the women who received sexual temperament scores of ≥ 19 and at least 14 were sexually considered to have hot temperament and sexual frigidity, respectively.

The participants were then examined in terms of sexual distress, depression, and anxiety. The subjects with the FSDS scores of < 15 and DASS-21 questionnaire score of ≤ 7 (i.e., sexual distress, moderate temperament, and stress, depression, and anxiety scores of ≥ 25, 20, and 14, respectively) and those meeting the other inclusion criteria were included in the study. The FSFI was completed by the participants in both groups.

The data were analyzed using the SPSS software, version 16. The normality of the data was investigated using the Shapiro-Wilk test. The mean and standard deviation were used to describe the data. Furthermore, Mann-Whitney U test, independent sample t-test, and Spearman’s rank correlation coefficient were used to analyze the data. P-value less than 0.05 was statistically significant.

Results

According to the statistical tests, the two hot- and cold temperament groups were homogeneous in terms of the age, age of the last child, marriage age, duration of marriage, number of children, type of child delivery, frequency of intercourses per month, and sexual distress, stress, depression, and anxiety scores (P<0.05, Table 1).

The total sexual function score was correlated with the hot temperament (P=0.001), indicating that those who obtained a greater sexual function score and had a better sexual function, were hot tempered. All subscales of sexual function, except for pain during sexual intercourse, were associated with sexual function (P<0.05). In this regard, there was no pain during intercourse in these individuals; however, libido, sexual stimulation, lubrication, orgasm, and sexual satisfaction were higher in those who had a higher sexual function score and were hot tempered.

The total score of sexual function had a significant relationship with cold temperament (P=0.016), suggesting that those who gained a higher sexual function score and had a better sexual function had a cold temperament. Accordingly, the subscales of libido (P=0.023), sexual satisfaction (P=0.018), and pain during sexual intercourse (P=0.005) in these individuals with cold temperament were associated with sexual function. In this respect, in cold temperament individuals who had higher sexual function score, sexual desire and sexual satisfaction were higher, while painful intercourse was also reported in these individuals (Table 2).

The comparison of sexual function and its subscales between the two groups with hot and cold temperaments showed that women with hot temperament had a significantly better sexual function (P=0.001, Table 3).