The results of this study showed that the effect of demographic variables on sexual satisfaction has been investigated using the odds ratio derived from logistic regression. As the findings show, the chance of having sexual satisfaction in women with university education is higher than illiterate women (P = 0.002, CI = 0.026 - 0.422, OR = 0.107) and 6.13 times more than women Their education at the level of the diploma is higher (P = 0.000, CI = 0.069 - 0.384, OR = 0.163). Because different job groups require different education, it was up to the researcher to unify groups in terms of their level of education. Also, the results showed that sexual satisfaction was higher in individuals aged 19 - 29 years of age and was lower in the age group 40 - 49 years. Addis et al. concluded in their study that younger women were more sexually active and gave sexual consent more frequently (
15). In a case study, Cohen et al. also found that sexual satisfaction was decreased with age increment (
16). Berek also reported that sexual desire and the frequency of intercourse gradually decreases with age (
17). The results of this study showed that the length of the marriage is also related to sexual satisfaction. This case study shows that sexual satisfaction is decreased with the increase of age.
Perhaps, the problems of life and the mental problems that result from it become more evident by increasing the length of the marriage and provoke a feeling of false dissatisfaction in couples. The researcher finds that in the early stages of marriage regarding sexual satisfaction, the feelings of men and women are at their strongest state, but gradually with the passage of time linked to the increasing age of men and women, sexual desire diminishes and, as a result, sexual interest becomes less intense. Of course, this does not mean that sexual satisfaction should reduce over time, but sexual satisfaction should remain throughout the life if it is not affected by other factors such as lack of marital understanding, illness or poor mental health. However, Halford found that sexual satisfaction was not reduced over time in most couples (
18). Liu et al. and Jose et al. also reported similar results (
19,
20). According to the results of this study, sexual satisfaction was shown to be related to the number of children in the marriage that with the increase in the number of children sexual satisfaction is decreased. In fact, it can be deduced that the frequency of sexual activity is a key factor in the prediction of sexual satisfaction in couples (
21). Over time, the frequency of sexual activity is decreased (
22). In addition, pregnancy may reduce the wife's sexual attractiveness to her husband; likewise, child-care and mental health are other negative factors. Sexual satisfaction appears to reduce through decreased sexual activity due to the longevity of marriage. Witting et al. found that nulliparous women had less sexual satisfaction due to painful intercourse compared to women who had children, regardless of the number of children, which was not consistent with the present study (
23). In this study, the age of the smallest child is related to the sexual satisfaction of the parents. It was shown that sexual satisfaction of the parent was decreased with the increase of the age of the child within the family. In fact, it can be deduced that as the child's age increases and related responsibilities increase alongside the increasing age of the parent; meanwhile, sexual satisfaction within marriage is decreased. In the present study, the age of the spouse has a significant effect on female sexual satisfaction, as it was shown that female sexual satisfaction was decreased when the husband’s age was increased. Therefore, the absence of age differences between couples could be considered an effective factor for sexual satisfaction. Men and women with a low age difference are more aware of each other and have the same interests and needs, and therefore, have a more mutual understanding of all aspects of life, including sexual matters. Research has shown that the family is threatened by increasing age gaps between spouses. The optimum range is between 0 to 10 years. A 20-year age gap shows that 50% of couples divorce (
24). Pothen et al. concluded that women who married men 5 - 6 years older than themselves derived the most sexual satisfaction (
25). Therefore, it appears that age differences can be an important factor in our understanding of different issues, including sexual issues. In this study, female sexual satisfaction was shown to vary according to the types and methods of contraception used. Condom users recorded the highest levels of sexual satisfaction. In Auslander’s research, the condom was the only contraceptive method that had an impact of increased sexual satisfaction. In his study, the sexual satisfaction of women who were sterile due to tube closure was less than by use of other methods. In the study of Costello et al., the sexual satisfaction of women with closed tubes was higher, which is not consistent with the results of the present study (
26). Also, in Cooper et al.’s study, a majority reported increased pleasure and frequency after tube closure (
27). The study also found that users of the pill recorded higher sexual satisfaction scores than those who used injectable ampules and intrauterine devices (IUDs). In the Carco’s study, women recorded an increased activity and libido whilst taking the pill. Merghati Khuei and Jafarpoor concluded that there was no significant relationship between any contraceptive method and sexual satisfaction (
28). Davis and Castano also showed that in general, some women experienced positive effects and others had negative effects, and there were also individuals who did not record any changes while used oral contraceptive methods (
29).