The present study was conducted to determine the relationship of repetitive negative thought and emotional regulation problems with sleep quality in pregnant women. The results showed a significant relationship between repetitive negative thoughts and sleep quality of pregnant women, which means the higher repetitive negative thoughts are, the poorer sleep quality of pregnant women will be, and the lower these thoughts are, the better their sleep quality will be.
The present study results so far agree with those of previous studies (
21,
25,
26). The results of a study by Slavish and Graham-Engeland to provide a model for prediction of sleep quality based on depression and anxiety mediated by rumination in a sample of 165 people, revealed a relationship between sleep quality and depressive and anxious mood through rumination (
27). The results obtained by Thomsen et al. in a sample of 126 individuals showed a significant relationship between sleep quality and rumination (
26). A study by Poormohseni to investigate and compare the role of repetitive negative thoughts in the form of worry and rumination in sleep disturbances in a sample of 60 students with normal and disturbed sleep showed that sleep disturbances are correlated with rumination, worry and its dimensions. Also, rumination and worry are able to predict sleep disturbances (
28). It can be concluded from comparison of previous studies (cited above) and the present study that repetitive negative thoughts and rumination have a negative role in sleep quality, and although the present study was conducted on a different population and in a specific setting, repetitive negative thoughts still had a negative role in sleep quality. Anxious and worried people have repetitive negative thoughts about adverse events (
22) and their possible occurrence. This is the case in pregnant women, especially about their infant’s future. These thoughts lead to emotional and physiological arousal (
23), which will lead to greater attention to environmental and personal stimuli, which may raise the individual’s heart rate and breathing, leading to reduced sleep quality. The confirmed relationship between repetitive negative thoughts and sleep quality in previous studies (
24), explains the present study results with regard to this relationship. This finding can be explained by the fact that what concerned the participating pregnant women in the present study was the absence of a clear picture of their infant’s circumstances after birth. On the other hand, many primiparous women have doubtful attitudes toward childbearing, for instance, would they be freer if they were not going to have a child at this time, and would the circumstances not be better and problems less in the future? Such concerns and ruminations lead to poorer sleep quality of mothers.
The present study results showed that emotion regulation has a relationship with depression, anxiety and stress (
29-
31), and these pave the way for insomnia (
32). Furthermore, review of a previous study shows that there is a relationship between emotion regulation cognitive strategies and sleep quality (
33). Other studies have reported that emotions affect sleep quality (
34). Therefore, this part of the present study results agrees with previous studies, except that the direct effect of emotion regulation on sleep quality is not significant, which means that emotion regulation problems have no direct effect on sleep quality, but have a significant effect through repetitive negative thoughts.
A person’s performance in psychological, cognitive, physiological and behavioral domains depends on emotion regulation, and proper emotion regulation leads to regulation of evaluations and subjective reactions, resulting in appropriate reactions in different aspects of life (
35). The results of previous studies have shown that emotion regulation has a relationship with depression, anxiety and stress (
29,
30).
Given their condition, pregnant women may experience some levels of depression, anxiety and stress (
36), and through these, emotion regulation problems can reduce sleep quality of these women, since these disorders can provide the context for reduced sleep quality (
37). According to the present study results, repetitive negative thoughts have a direct and significant effect on sleep quality, but the direct effect of emotion regulation on sleep quality is not significant, which means that emotion regulation problems have no direct effect on sleep quality, but an indirect effect through repetitive negative thoughts. It is believed that depression, anxiety, and stress affect sleep quality (
38). Furthermore, anxious and worried people have repetitive thoughts about negative events (
39), and worry about their happening. The same applies to pregnant women who worry about their child’ future. These thoughts cause emotional and physiological arousals (
40), which in turn make the individual pay greater attention to environmental and personal stimuli, which may be rather absorbed by heart rate and breathing, and their irregularity can lead to reduced sleep quality. Previous studies have shown that there is a relationship between repetitive thoughts and sleep quality (
19). According to Harvey’s Theory, repetitive negative thoughts (worry and rumination) about the amount of sleep lead to emotional arousals and disturbances, and this entails mistaken bias in the perception of sleep function and duration, resulting in persistence of sleep disturbances. The present study results somehow support Harvey’s theory. Review of previous studies shows that people’s worry leads to cognitive-anxious arousal, resulting in increased autonomic nervous system activity.
Since the present study enrolled pregnant women from Kermanshah, care should be taken in generalization of the results. It is better if a similar study is conducted in other communities and with a larger sample size to enhance generalizability of the results.
It is recommended that future studies consider the cause and effect relationships of these variables in the form of an experimental project. Moreover, since the present study healthy pregnant women participated in this study, it is recommended that future studies include pregnant women with particular diseases as well as infertile women. Given the present study results, to improve pregnant women’s sleep quality, it is recommended that the role of emotion regulation problems and repetitive negative thoughts be taken into account. The present study was conducted in Kermanshah province using convenience sampling, and thus care should be taken in the generalization of the results, further studies in other communities are needed.
4.1. Conclusion
According to the results obtained, sleep quality of pregnant women is related to repetitive negative thoughts and emotion regulation problems. Moreover, emotion regulation problems reduce sleep quality when there is a high level of repetitive negative thoughts. Therefore, the role of repetitive negative thoughts should be considered in solving sleep problems. Hence, health authorities are recommended to use psychiatric services to improve the sleep quality of pregnant women.