1. Introduction
ne of the common problems during pregnancy is the fear of childbirth, which affects 6% to 10% of women [1]. The symptoms include physical complaints with no medical justification, experiencing severe negative emotions, nightmares, and attention and concentration problems. However, one of the most critical consequences of childbirth fear is the willingness to have a cesarean section, despite the lack of medical issues for vaginal childbirth [2]. Fear of childbirth may have risks for the mother and her baby, as well as distress and concerns for the family and medical staff. Therefore, it seems necessary to identify the factors affecting the emergence or continuation of the fear. In this regard, the present study aimed to investigate the role of experiential avoidance, cognitive fusion, and difficulty of emotional regulation in childbirth fear among primigravid women in Rasht City, Iran. 
2. Methods
This study was cross-sectional analytical research. The study population consisted of primigravid women referring to Alzahra Medical Educational Center in Rasht. Considering the inclusion criteria, 300 women were included using a simple random sampling method. The inclusion criteria were aged 18-35 years, the pregnancy age at 28-36 weeks, lack of previous pregnancy and childbirth, absence of psychotic disorder, drug abuse, absence of personality disorder, and willingness to participate in the project and answering the questionnaires. 
The first part of the questionnaire collects demographic information, including age, marital status, duration of the marriage, education, employment, the decided delivery type, income level, spouse's satisfaction with pregnancy, single or twin pregnancy, the only pregnant person in the family. The second part of the questionnaire included an experiential avoidance questionnaire. This questionnaire measures experiential avoidance acceptance and psychological inflexibility. The third part included difficulty in emotional regulation. The fourth part included Gillanders cognitive fusion. The fifth part was fear of childbirth. 
After collecting data, they were analyzed in SPSS. The descriptive statistical indicators (mean, median, frequency, and standard deviation), the Pearson correlation coefficient, and multivariate regression step by step were used to analyze data. 
3. Results
Demographic information showed that the minimum age of women was 15 years, and the maximum was 47. Their mean age was 28 years. Regarding the participants' education, 26 women (8%) were illiterate, 43 (14%) had a middle school diploma, 128 (42.7%) had a diploma, and 102 (34%) had academic degrees. Also, 65 women were employers, and 235 housewives. The findings showed a significant reverse relationship between income and fear of childbirth (P<0.05, r=-0.22). Predicting fear of childbirth based on experiential avoidance, cognitive fusion, and difficulty of emotional regulation, the subcomponent of cognitive fusion was calculated was equated in the first step from the variable of fusion, and from the experiential avoidance in the second step and could explain 12% of the variance of fear of childbirth (R2=0.12).  The significant values (P<0.0005) of 1-way analysis of variance (F) in all steps indicated that the regression model was significant. Moreover, the variables' standardized beta coefficients showed that cognitive fusion had the greatest contribution to the explanation of fear of childbirth (beta=0.32). The significant value of t (P<0.0005) indicated that this contribution was significant. No other variable entered into the model after these two variables, which showed that among the three predictor variables, the variable of difficulty of emotional regulation and its variables failed to enter into the model due to a lower percentage of explaining the variance of fear of child than the two other variables.  
4. Discussion and Conclusion
Experiential avoidance and cognitive fusion can predict fear of childbirth in primigravid women. The findings of this study can be used as a guide to treat psychological problems in primigravid women, especially fear of childbirth. Also, behavioral-cognitive therapies can be used to change or accept the thoughts related to fear of childbirth. In addition, acceptance- and commitment-based treatment can help people increase their psychological flexibility (decreasing experiential avoidance and cognitive fusion) rather than suffering from inner experiences such as thoughts, memories, emotions, etc. Therefore, it is suggested that psycho-educational courses be used to reduce experiential avoidance and cognitive fusion and consequently fear of childbirth. 

Ethical Considerations
Compliance with ethical guidelines
This study was approved by the Ethics Committee of the Guilan University of Medical Sciences (Code: IR.GUMS.RES.1398.250).

Funding
This study was supported by the Deputy for Research and  Technology of Guilan University of Medical Sciences (No: 98050514).

Authors' contributions
Conceptualization, visualization, project administration: Kourosh Delpasand; Analysis and validation: Habib Eslami and Mehrdad Ghanbarpoor Ganjari; Methodology, investigation and supervision: Samaneh Mirzaei, Mehrdad Ghanbarpoor Ganjari and Mahboubeh Sarparast; Original draft preparation: Samaneh Mirzaei, Ayemeh Hassanpour, Mehrdad Ghanbarpoor Ganjari; Editing and review: Seyyed Hamidreza Fallah Mortezanejad, Samaneh Mirzaei, Mehrdad Ghanbarpoor Ganjari.

Conflicts of interest
The authors declared no conflict of interest.

Acknowledgements
All authors would like to thank the Vice-Chancellor for Research and Technology and the Student Research Committee of Guilan University of Medical Sciences for their help.


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