Data file for open access.

Introduction
Fear of Childbirth (FOC) is the most common psychological problem among pregnant women, especially in primipara women who are more likely to fear the unknown delivery process. The causes of FOC are complex and influenced by various factors, but the impact of menstruation-related factors remains unclear. Therefore, this study aims to understand the current situation of FOC in primiparous women during late pregnancy, investigate the influencing factors of FOC, and further explore the correlation between premenstrual syndrome (PMS) and FOC.
Methods
This study is a multicenter cross-sectional study. A convenience sampling method is used to select 597 primiparous women who attend regular prenatal check-ups at three healthcare institutions in Nantong City, Jiangsu Province, China, between December 2023 and February 2024. Participants are required to complete the general information questionnaire, Premenstrual Syndrome Scale, Childbirth Attitude Questionnaire, Perceived Social Support Scale, Pittsburgh Sleep Quality Index, and Marital Adjustment Scale. Mann-Whitney U test and Kruskal-Wallis test are used to access the between-group differences. Multiple linear regression is used to analyze the influencing factors of FOC. Spearman correlation examines the relationship between PMS and FOC.
Results
The results show that 46.73% of primiparous women experience FOC. Multiple linear regression analysis shows that dysmenorrhea, unintended pregnancy, PMS, social support, sleep quality, and marital relationship are significant factors influencing FOC (P < 0.05). Additionally, PMS is moderately positively correlated with FOC (r = 0.549, P < 0.01).
Conclusion
Our study results indicate that the social issue of FOC deserves attention. Clinical healthcare professionals should focus on the physical and mental well-being of pregnant women, particularly those with PMS. They should enhance prenatal psychological assessments and provide targeted emotional support based on individual circumstances, helping these women better cope with childbirth, improve their childbirth experience, and ensure maternal and infant health.