Study design and literature search

This scoping review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews⁹.

A protocol was created and registered with the University hospital Medical Information Network (UMIN) Center on 9 September 2024 (UMIN Study ID: UMIN000055460). A literature search was conducted using CHNAHL, the web version of the Central Medical Journal on 13 September of the same year, and PubMed on 17 September of the same year, and data extraction was completed in September. A health science information specialist with experience in literature searches was provided with guidance for the search. The eligibility criteria were as follows: studies that employed decision support interventions targeting pregnant women considering epidural analgesia, regardless of their pregnancy stage or whether spontaneous or induced labor was occurring, in comparison with standard care or not employing decision-making interventions. Reviews were excluded.

With regard to definitions, epidural birth was noted as ‘Vaginal birth with epidural anesthesia’ while decision support was noted as ‘To support the right of women/families to actively participate in decisions about their care¹⁰, this study specifically addresses support for deciding whether to receive epidural analgesia’.

Data extraction, synthesis, and presentation

This study was prepared following the reporting guidelines for scoping reviews (PRISMA-ScR)⁹ using a population, concept, context approach: the ‘population’ was ‘low-risk pregnant women considering their mode of delivery’, the ‘concept’ was ‘what is known about decision aids during pregnancy and their effectiveness’, and the ‘context’ consists of ‘hospitals and clinics that administer anesthesia during pregnancy and childbirth’. The search terms set for each database included the following keywords: ‘anesthesia’, ‘decision-making’, and ‘pregnant women’ (Supplementary file Table 1). The literature in English was comprehensively reviewed. Based on the article eligibility criteria, two authors screened the titles, abstracts, and full texts and then selected eligible articles for analysis. The authors settled differences in opinions through discussion and then decided the target articles.

The extracted data were: authors, publication year, country, sample characteristics, timing of the intervention, intervener, content of the interventions for the intervention and control groups, outcome measures, and presence of any significant differences. The analysis was based on the following research questions: 1) ‘What methods are used to support decision-making?’; 2) ‘When is the most effective time to provide decision support?’; 3) ‘What indicators are used to measure the effectiveness of decision support?’; 4) ‘Who are the effective implementers of decision support?’; and 5) ‘What are the effective methods for decision support?’.

What methods are used to support decision-making?

Of the 15 studies, leaflets were the most common intervention used (nine studies)^{11,15,16,18,21-25} followed by counseling (four studies)^14,23-25, discussion (three studies)^12,13,20, lectures^13,14, video^16,23, group education^17,19, audio guide^21,22 (two studies each) and presentation¹². Four of the 15 studies clearly indicated that the decision support used a method based on shared decision-making (SDM)^14,16,24,25.

When is the most effective time to provide decision support?

The timing of intervention was from early pregnancy, mid-pregnancy, and late pregnancy onward in two^17,18, three^20,23,24, and nine studies^{12-16,19,21,22,25}, respectively, while the rest were conducted before birth; however, the timing was unclear¹¹ (one of these studies was literature questioning knowledge and included postpartum participants¹¹). The timing of intervention was more frequently performed in mid or late pregnancy than in the early stages. No studies compared the effects of different intervention timings.

What indicators are used to measure the effectiveness of decision support?

The following eight items were used: satisfaction with the intervention^{12,15,16,18,21,22,24}, satisfaction with the birth experience^{12-14,16,17,24}, knowledge and misunderstandings^{11,12,15,19,22,23}, anxiety and fear^13,21,22, conflict^15,21,22, degree of participation in the decision-making process^21,22, feeling supported by others, control of emotions and attitudes¹⁴, and planned to or decided to use epidural analgesia during delivery^{11,13,15,17,20,21,23-25}.

Who are the effective implementers of decision support?

Regarding the personnel who implemented the intervention, of the 15 studies, the interventions were carried out by midwives alone in six studies^{13,14,17,20,24,25}, a doctor alone in one¹⁹, a medical team consisting of nurses or midwives and a doctor in two^12,23, and a leaflet or other media alone in six^{11,15,16,18,21,22} without involvement of any professionals. No studies have compared the effects of interventions between professions (Table 1).

What are the effective methods for decision support?

Satisfaction with the intervention

A total of seven studies^{12,15,16,18,21,22,24} measured satisfaction, and the interventions implemented were a combination of presentation and discussion¹², a leaflet only^15,18,24, a combination of leaflet and video¹⁶, a combination of leaflet and audio guide²¹, and a combination of leaflet, video and counseling²⁴. Of these, four studies^12,15,16,21 reported a significant difference in effectiveness, and the interventions implemented in effective studies were a combination of presentation and discussion¹², a leaflet only¹⁵, a combination of leaflet and video¹⁶, and a combination of leaflet and audio guide²¹. Even in three studies without significant differences, the proportion of people who felt satisfied was higher than in the control group^18,22,24. Media-only interventions were not associated with the decrease in satisfaction^15,16,21, and compared with providing only information, a combination of a leaflet and video incorporating SDM techniques was associated with higher satisfaction with the intervention¹⁶ (Table 2).

Satisfaction with the birth experience

Six studies^{12-14,16,17,24} measured satisfaction with the birth experience, and the interventions implemented were a combination of presentation and discussion¹², a combination of group education and discussion¹³, a combination of counseling and lecture¹⁴, a combination of leaflet and video¹⁶, group education¹⁷, and a combination of leaflet and counseling²⁴. Of these, three studies^12,14,16 revealed a significant difference in effectiveness, and the interventions implemented in studies where an effect was found were a combination of presentation and discussion by nurses and anesthesiologists¹², a combination of counseling and lecture by midwives¹⁴, or a combination of leaflet incorporating SDM methods and video¹⁶. No studies have reported results on group education increasing satisfaction with birth experience^13,17. Two studies implemented interventions based on SDM methods, and both results demonstrated that the intervention group was significantly more effective than the control group^14,16 (Table 2).

Knowledge and misunderstandings

Eight studies^{11,12,15,18,19,21-23} measured knowledge and misconception changes due to decision aids, and the interventions implemented were leaflets only^11,15,16, a combination of presentations and discussion¹², group education¹⁹, a combination of leaflets and audio guides^21,22, and a combination of videos, leaflets, and counseling²³. Six^{12,15,18,19,21,23} of these studies revealed significant differences in effectiveness. All of the methods were effective; however, some studies that used leaflets alone or a combination of leaflets and audio instructions demonstrated no significant differences. In the study that reported no significant difference^11,22, only leaflets were distributed to the control group, and knowledge scores increased in both groups¹¹. As for satisfaction, knowledge scores tended to increase even with media-only interventions^15,18,21 (Table 2).

Anxiety and fear

Regarding anxiety and fear of childbirth, three studies used it^13,21,22: two used a combination of a booklet and an audio guide^21,22, and the remaining one combined lecture and discussion¹³. None of the three studies found a significant reduction in anxiety or fear, and no significant difference was observed between the two groups (Table 2).

Conflict

Three studies^15,21,22 measured changes in conflict, and the intervention implemented was either a leaflet only or a combination of a leaflet and an audio guide. Of these, one study revealed a significant difference in effectiveness, and the intervention implemented in the effective study was a leaflet only¹⁵. In both studies^21,22 reporting no significant difference, only leaflets were distributed to the control group, and conflict levels decreased in both groups. As for satisfaction, knowledge, and misunderstandings, conflict levels tended to decrease even with an intervention that used only media (Table 2).

Level of involvement in the decision-making process

Two studies^21,22 measured participation in the decision-making process, and both interventions combined a leaflet and an audio guide: one showed a significant difference and one reported that the intervention group was significantly more likely to report making the decision themselves after seriously considering their care providers’ opinion compared to the control group who reported that they had made their labor analgesia decision by themselves²¹. This indicates that the decision-making support had been implemented effectively. In the study that revealed no significant difference, the control group was also given only leaflets, and the conflict level decreased in both groups²². Media-only interventions tended to increase participation in the decision-making process²¹ (Table 2).

Feeling supported by others, control of emotions and attitudes

One study measured the perceived support from others and emotional and attitudinal regulation, which combined counseling and verbal explanations and found a significant difference in effectiveness. Moreover, the intervention in this study was based on SDM methods¹⁴ (Table 2).

Planned to or decided to use epidural analgesia during delivery

Nine studies^{11,13,15,17,20,21,23-25} analyzed whether epidural analgesia was planned to be used or used during labor, and the interventions used were a leaflet only^11,15; a combination of group education and discussion¹³; group education¹⁷; a combination of leaflet and audio guide²¹; discussion²⁰; a combination of video, leaflet, and counseling²³; and a combination of leaflet and counseling^24,25. Two studies reported that the planned or actual use of epidural analgesia was significantly lower in the intervention group, and the interventions used were a combination of group education and discussion¹³ or a combination of leaflet and counseling²⁴. Conversely, three studies demonstrated that the planned or actual use of epidural analgesia was significantly higher in the intervention group, and the interventions used were group education¹⁷; a combination of video, leaflet, and counseling²³; or a combination of counseling and leaflet²⁵. The combination of counseling and leaflets increased the number of women who combined epidural analgesia with non-pharmacological methods such as breathing techniques²⁵. Of the three studies reporting that the planned or actual use of epidural analgesia was significantly higher, one was a US study with a Hispanic cohort. The study background was that Hispanics were already using epidural anesthesia at a low rate due to factors such as medical disparities²³. In another case that increasingly used anesthesia, the intervention reduced the use of epidural anesthesia; however, the use of anesthesia in the control group was low, to begin with. Therefore, the intervention group used more anesthesia than the control group¹⁷. In the remaining case with high anesthesia use, the intervention decreased the desire to use anesthesia in both groups; however, more people wanted it in the intervention group than the control group at baseline²⁵ (Table 2).

Literature summary

This scoping review determined what is known about decision aids and their effects on women choosing epidural analgesia during delivery. A total of 15 articles, including randomized controlled trials, non-randomized controlled trials, and cohort studies, were included for analysis based on the eligibility criteria.

Decision aid methods included leaflets, counseling, lectures, presentations, discussions, videos, group education, and audio guides. These were mainly delivered during the second or third trimester of pregnancy. Most were delivered by nurses; however, some were delivered by doctors or health professional teams and by media-only. When interventions were divided into those providing media such as leaflets and those involving expert interaction such as discussion or counseling, media-only interventions increased satisfaction, knowledge (and reduced misconception levels), participation in the decision-making process, and reduced conflict levels, whereas adding expert interaction further increased satisfaction.

Effectiveness of decision support

Regarding the intervention timing, most articles included were in the middle or late stages of pregnancy, rather than in the early stages. Previous studies have reported that late pregnancy was considered the ideal time to be given information about labor analgesia²⁶. Furthermore, 73% of women stated that they would want counseling on analgesic options from their obstetric providers during the second or third trimester²⁷. Furthermore, of the studies included in this review, 66% of women wanted information about pain relief during labor and the opportunity to discuss the information given in the late stages of pregnancy¹⁵. Given the above studies, decision support interventions may be better provided in the middle to late stages of pregnancy¹⁸, when women can particularly consider labor as their concern, rather than in the early stages of pregnancy. Regarding the implementers of decision support, many interventions in this study were provided by nursing professionals, such as midwives and nurses; however, a significant difference was detected between anesthesiologists alone and nursing professionals alone, with some interventions being effective and others not, and the results were mixed. In addition, results of the media-only intervention and the intervention involving midwives did not provide indicators of conflict, participation in the decision-making process, a sense of support from others, or control of emotions and attitudes, and comparisons between professionals were not possible; therefore, concluding which professional provides better decision-making support is challenging.

The literature involved in this study reveals that satisfaction or knowledge scores did not decrease or conflict levels increase in items such as information satisfaction, knowledge and misunderstandings, and conflict, when media such as pamphlets were used alone. Consequently, depending on the content and purpose of the media provided, intervention by medical professionals is not essential and that effects can be obtained with media alone.

The results showing a tendency for knowledge to improve by intervention, as well as the results of an increase in the sense of support from others and the sense of control over emotions and attitudes, suggest that in case of available information, it is easier to feel supported during labor and the possibility of using the information obtained on one’s own. Additionally, for the planned or actual use of epidurals, interventions may reduce the desire to use or use them, and increased knowledge on the risks and side effects of epidurals may increase the possibility of avoiding the use of epidural anesthesia. Conversely, the result that the intervention group used anesthesia more significantly than the control group in terms of planned or actual use of epidural anesthesia was because Hispanics use anesthesia less frequently during delivery than Whites. The purpose of the intervention may have differed depending on the original use of epidural anesthesia during delivery in the field and the target population. That may have resulted in different results. Although the intervention is the same, the expected effects may differ depending on the study background. In fear and anxiety, no method revealed a clear difference. Even if the patient temporarily calms down by asking questions, gaining knowledge, or talking, anxiety is likely to be remembered again as time passes or time approaches, and may be difficult to resolve with the intervention.

In recent years, SDM²⁸, which refers to the process in which clinicians and patients work together to clarify the treatment, the management, or self-management support goals and share information about options and preferred outcomes to reach mutual agreement on the best course of action, has also attracted attention. All literature that clearly defined methods based on SDM in this study showed significant differences in satisfaction with the birth experience and feeling supported by others, control of emotions and attitudes; however, the number of studies is small. Therefore, the effects cannot be clarified. In addition, although research on SDM has focused mostly on the creation of tools to support patient involvement in decisions and much less on how to create a culture where professionals espouse SDM as a skill and routinely use these tools²⁹, the universal methodology cannot be clarified. Therefore, research methods vary depending on the literature, and the effects may differ, warranting further research.

Limitations

This review has limitations in generalizing the results of simple comparisons because the scales used to measure effectiveness were non-uniform. In addition, for some outcome items the literature articles are few, and the results have not been fully examined. Regarding the intervention timing, many studies have been conducted in the mid to late stage of pregnancy, indicating that intervention during this period is effective. However, no studies have compared the intervention timing; thus, further research is needed. This study did not evaluate the risk of bias; therefore, the results of the included literature may have been over- or under-evaluated. The present review only referred to studies on epidural anesthesia and excluded other pharmacological pain relief methods.