This study used data from the 8th KNHANES (2019-2021) to identify the influence of oral health problems and dental care usage behaviors on EQ-5D among women with pregnancy and childbirth experience.

First, regarding EQ-5D according to sociodemographic characteristics, all variables showed significant differences between groups. Age, family income (5 quintile), status of basic living subsistence, and education level were identified as influencing factors of EQ-5D. The results showed that the age range of 20–59 years old had a significant influence on EQ-5D, with the highest among women aged 40–49 years old and the lowest among those aged 80–89 years old. Park and Park [17] reported that EQ-5D was higher among those with higher income levels, while Kim and Lim [18] reported that it was lower among those with lower income and education levels and among recipients of basic living subsistence. Kim [19] conducted a study on low-income older female adults and found that low-income older female adults with a lower education level and older age had a lower EQ-5D. The results in these studies were consistent with those in this study. People aged 40–49 years old, on average, are in the most stable period of their lives, as they have jobs, steady income, and a better living environment, enhancing their quality of life by influencing income and education levels. Meanwhile, people aged 80–89 have a lower quality of life as they are no longer economically active.

Regarding EQ-5D according to oral health problems, all variables showed significant differences between groups. Those with better self-perceived oral health and fewer chewing problems, complaints of chewing discomfort, and speech problems showed higher EQ-5D. The influencing factors of EQ-5D were identified to be chewing problems, complaints of chewing discomfort, and speech problems. Kim and Lee [20] reported that people with poorer subjective oral health status and speech discomfort had a higher incidence of periodontal disease. Additionally, Choi et al. [21] confirmed an association between oral health status and EQ-5D and reported that chewing and speech problems were significantly associated with all five components of the EQ-5D. These results were consistent with the findings in this study. Lee [22] reported that the influencing factors of the EQ-5D were gender, age, income level, education level, chewing and speech problems, toothache experience, and subjective oral health status, which was partially consistent with the findings in this study. Moreover, Panchbhai [23] also reported that physical and oral health are factors that affect quality of life, while poor oral health, chewing and speech problems, and pain can influence quality of life. Based on such findings, it can be interpreted that oral health is associated with overall health and that objective symptoms and subjective perceptions of oral health status have a significant influence on health. Kim and Lim [24] found that objective oral health indicators from experts and subjective oral health status are associated, suggesting that people with better perceived health are more likely to have higher objective oral health indicators. Therefore, oral health care is essential for women with pregnancy and childbirth experiences to live a healthy life. Additionally, managing objective symptoms and perceiving oneself as having good oral health are both important.

Regarding EQ-5D according to dental care usage behaviors in the past year, all variables except treatment of simple cavities showed significant differences between groups. Those who had no toothache experience, no dental check-up, and no treatment of periodontal disease or root canal in the past year had a higher health-related quality of life. Shin and Kim [25], Sung [26], and Son [27] reported that dental care usage is associated with health-related quality of life, which was consistent with the findings in this study. However, not all variables were significant influencing factors in EQ-5D. A systematic review by Rocha et al. [28] found that dental care usage during pregnancy varied from 16 to 83% and suggested that psycho-behavioral factors such as socioeconomic factors, beliefs about oral health and pregnancy, and oral health behaviors play an important role as determinants of dental care. This suggests that various intrinsic factors may influence dental care usage; future studies must compare the health-related quality of life of women who are pregnant and women with pregnancy and childbirth experiences.

This study used only secondary data from KNHANES and did not include women without pregnancy and childbirth experiences or men in the comparisons. Therefore, there are limitations in representing the population. Moreover, menopause is also closely associated with oral health in women due to hormonal changes, poor nutrition, and poor oral hygiene. The average age of menopause is 50; thus, the study population of this study included women who were experiencing menopause. A previous study on postmenopausal women reported that 70% had not had a dental check-up in the past year and that those who did not have a dental check-up were less likely to practice oral health care behaviors than their counterparts [29]. In the future, comparative studies between groups such as women of childbearing age, pregnant women, postpartum women, and postmenopausal women based on the lifecycle of women should be conducted to develop systematic and continuous oral health education programs and alternative approaches to oral health policies.

Nevertheless, the significance of this study is that it confirmed the association between oral health status and dental care usage behaviors of women with pregnancy and childbirth experiences and their health-related quality of life, suggesting the need for continued oral health care throughout the lifecycle of women. Moreover, the findings in this study are expected to be used as basic data for improving oral health programs for women.