Expecting the uncertain: The applicability of the intolerance of uncertainty model on fear of childbirth

Abstract

A considerable number of pregnant women experience fear of childbirth (FOC), characterized by worries and fear of the unpredictable. Despite this, the psychological processes in FOC have received notably little attention. The aim of this study was to advance the understanding by exploring the applicability of the Intolerance of Uncertainty (IU) model on FOC. Anonymous data was collected in a sample of pregnant women (N = 357) with varying levels of FOC. Analyses supported the associations between FOC and all proposed psychological processes: IU, negative problem orientation, positive beliefs about worry and avoidance of inner experiences. The exploration of potential mediators of the relation between IU and FOC revealed that, of the three processes from the model, only positive beliefs about worry were a mediator, and more specifically, a partial mediator between IU and FOC. These findings add to the theoretical understanding of FOC, by indicating that the role of IU may be similar to other conditions inflicted by worry and anxiety, which may inform treatment development.

Keywords:

• Fear of childbirth
• intolerance of uncertainty
• fear
• childbirth
• pregnancy

Introduction

Giving birth is a life-changing event. Each childbirth is unique, and it is impossible to foresee the exact progression of labor. While most women are facing childbirth with predominantly positive expectations, feelings are often mixed; it is not unusual to suffer from worries and fear regarding aspects such as the associated unpredictability [1]. Although giving birth is relatively safe in high-income countries [2], a considerable number of pregnant women experience substantial levels of fear of childbirth (FOC).

Fear of childbirth may range from milder forms to clinical levels. Clinical FOC has been defined as “a disabling fear that interferes with occupational and domestic functioning, as well as social activities and relationships” [3]. The prevalence of clinical FOC in low-risk pregnant women has been estimated to 11–16% [4,5], although prevalence rates vary depending on definition and measures [6]. It should however be noted that milder forms of FOC is far more common, as most pregnant women experience some degree of fear.

In addition to the suffering related to the fear and worry itself, FOC has been linked to adverse perinatal outcomes such as stress, anxiety, depression, lack of social support, and a risk of post-traumatic stress symptoms [7]. There is also a risk of prolonged labor, obstetric complications, heightened use of anesthetics [8], and emergency cesarean sections [9]. An enhanced understanding of FOC would open possibilities for preventing adverse consequences early on, by pointing out potential targets of treatment for FOC.

Despite high occurrence and apparent negative consequences, the psychological processes in FOC have received notably little attention. In an extensive review of the literature, Rondung and colleagues [10], suggested transdiagnostic processes (i.e. occurring across disorders) in anxiety disorders as a potential area for further investigation. Not surprisingly, considering the inherent unpredictability of labor, intolerance of uncertainty (IU) was pointed out as one such transdiagnostic process. IU refers to the tendency of worrying about unpredictable and uncertain events, and their hypothetically negative consequences [11]. Indeed, emerging evidence points at a link between IU and FOC [12,13]. Yet, research is sparse and the specific role of IU in FOC remains unclear.

The most established model of IU is the IU-model [11,14] where IU is illustrated as a key maintaining process of generalized anxiety, directly linked to worry. There is also an indirect link, through three transdiagnostic processes: 1) negative problem orientation, i.e. perceiving problems as threatful and difficult to deal with, 2) positive beliefs about worry, i.e. recognizing worry as a beneficial problem-solving strategy, and 3) avoidance of negative inner experiences, more specifically avoiding distressing thoughts [15]. These three psychological processes have in previous studies been shown to be associated with excessive worry [11,16–18], but have not simultaneously been studied in relation to FOC. Considering the prominent fear of uncertainty characterizing FOC, it deems logical to explore the applicability of this model on FOC.

Aim

The aim is to advance the understanding of Fear of Childbirth (FOC), by exploring the association between Intolerance of Uncertainty (IU) and FOC in line with proposed links in the IU-model (Figure 1).

Figure 1. Proposed links between IU and FOC, with negative problem orientation, positive beliefs about worry and avoidance of inner experiences as potential mediators.

Research questions

1. Are there associations between (a) IU and FOC, and (b) the processes within the IU-model, in other words negative problem orientation, positive beliefs about worry and avoidance of inner experiences, and FOC?

2. Does any of the psychological processes mediate the possible association between IU and FOC in line with the IU-model?

Material and methods

This cross-sectional study is based on anonymous data collected during fall 2022, as part of a master thesis in psychology [19]. As the psychological processes are expected to be similar independent of levels of FOC, a general sample of pregnant women was used, where all levels of FOC were represented. Women were recruited via a web-survey, advertised via social media (n = 344), posters at health care institutions (n = 3), and in public areas (n = 10). Eligible participants were directed to a webpage where they were informed about the study and consented to participate. Principles of the declaration of Helsinki were followed and as all data was anonymous, lacking information that would enable identification of participants, ethical approval was not required.

Participants

Eligible participants were individuals >18 years old in the third trimester of pregnancy. The sample consisted of women (n = 355) and non-binary individuals (n = 2), primiparous/multiparous (n = 180/177), in ages 20-43 (M = 31.2), and gestational week 28–42 (M = 35). Most participants were in a relationship (n = 352). Fear of childbirth (FOC) varied between 0 and 100 (M = 32, SD = 26.51) and 22% (n = 77) reached the proposed cutoff for clinical FOC at ≥54 [20].

Measurements

Swedish versions of all measurements were used. Demographic questions covered age, gender, relationship status, gestational week and previous childbirth(s).

Fear of childbirth was assessed with the Fear of Birth Scale [FOBS, 22]. The scale consists of two items measuring worry and fear of the approaching birth on two separate visual analogue scales between 0=“calm”/”no fear” and 100=”worried”/”strong fear”. The total score is the sum of the two items divided by two resulting in a total range of 0–100 with higher scores indicating higher levels of FOC. FOBS has shown good psychometric properties and has been used in Swedish samples [13,21]. In the current study internal consistency was good with α=.91.

Intolerance of uncertainty was assessed with the 12-item version of the Intolerance of Uncertainty Scale [IUS-12, 24]. The scale consists of items such as “Unforeseen events upset me greatly”, and answers are given on a Likert scale between 1=”not at all characteristic of me” and 5=“entirely characteristic of me”. The total score ranges between 12–60 with higher scores indicative of higher levels of IU. The IUS-12 has shown good psychometric qualities [22–24] and in the current study internal consistency was good with α = 0.90.

Negative problem orientation was assessed with the Negative Problem Orientation Questionnaire [NPOQ, 26] which consists of 12 statements such as “I see problems as a threat to my well-being” rated on a Likert scale between 1=”not at all true” and 5=”extremely true”. The total score ranges between 12–60 with higher scores indicative of a greater negative problem orientation. The scale has shown good psychometric properties [25–27]. In the current study, internal consistency was good with α = 0.94.

Positive beliefs about worry were assessed with the Why Worry II [WW-II, 28]. The scale entails 25 items such as “The act of worrying itself can prevent mishaps from occurring” rated on a Likert scale between 1=”not at all” and 5 = ”all the time”. The total score ranges between 25–125 with higher scores indicative of more positive beliefs about worry. The scale has shown good psychometric qualities and has been used in Swedish samples [13,28]. In the current study, internal consistency was good with α = 0.95.

Avoidance of inner experiences was assessed with the Brief Experiential Avoidance Questionnaire [BEAQ, 30]. The BEAQ entails 15 statements such as “I go out of my way to avoid uncomfortable situations” rated on a Likert scale between 1=”strongly disagree” and 6=”strongly agree”. The total score ranges between 15–90 with higher scores indicative of a greater tendency to avoid inner experiences. The scale has shown good psychometric properties [29]. In the current study, internal consistency was good with α = 0.87.

Statistical analyses

Analyses were performed with the Statistical Package of Social Sciences (SPSS) 28.0. To address the first research question, Spearman’s correlation analyses were used due to non-linearity between the processes [30]. To explore this question further, a multiple regression model was performed, with FOC as dependent variable, and negative problem orientation, positive beliefs about worry, and avoidance of inner experiences as independent variables. To address the second research question, a multiple mediation analysis was performed through the SPSS Process Macro [31], where positive beliefs about worry and avoidance of inner experiences were evaluated as possible mediators of the relationship between IU and FOC.

Results

Associations between fear of childbirth, intolerance of uncertainty and processes within the IU-model

The correlational analyses revealed significant associations between FOC and all proposed psychological processes (Table 1). Higher ratings of FOC were associated with higher levels of IU, as well as with greater negative problem orientation, higher levels of positive beliefs about worry and a greater tendency to avoid inner experiences. The correlations between the processes in the IU model and FOC were weak (0.22–0.35), and the correlations between the processes within the IU model were moderate (0.47–0.67).

Table 1. Correlations between fear of childbirth and the processes within the IU-model.

	M	SD	1	2	3	4	5
1. Fear of childbirth (FOBS)	32.00	26.51	–	0.35*	0.22*	0.32*	0.28*
2. Intolerance of uncertainty (IUS-12)	29.17	8.63		–	0.67*	0.55*	0.53*
3. Negative problem orientation (NPOQ)	21.63	8.63			–	0.51*	0.54*
4. Positive beliefs about worry (WW-II)	46.60	16.03				–	0.47*
5. Avoidance of inner experiences (BEAQ)	38.38	12.28					–

FOBS, 0-100; IUS-12, 12-60; NPOQ, 12-60; WW-II, 25-125; BEAQ, 15-90; *p < .001.

The multiple regression analysis showed that negative problem orientation, positive beliefs about worry and avoidance of inner experiences, together explained 11.7% of the variance in FOC (F(3, 347) = 15.40, p < .001). Positive beliefs about worry and avoidance of inner experiences were significantly associated with FOC, however, negative problem orientation was not when including all processes in the same model (Table 2). Hence, pregnant individuals with positive beliefs about worry and a tendency to avoid distressing internal experiences, were more likely to experience FOC.

Table 2. Multiple regression with the processes in the IU-model on FOC.

	B	SE	β	R^2
Negative problem orientation (NPOQ)	0.15	2.33	0.00	–
Positive beliefs about worry (WW-II)	9.27**	2.44	0.22**	–
Avoidance of inner experiences (BEAQ)	5.53*	2.00	0.17*	–
				0.12

NPOQ, 12–60; WW-II, 25–125; BEAQ, 15–90; *p < .01, **p < .001.

Mediators of the association between intolerance of uncertainty and fear of childbirth

Based on results of the regression model, positive beliefs about worry and avoidance of inner experiences were proposed to mediate the relationship between IU and FOC. Table 3 displays results of the multiple mediation model which showed a decrease in the direct effect (c, β = 0.34, p<.001) compared to the indirect effect (c’, β = 0.23, p<.001), however still significant. Standardized regression weights are illustrated in Figure 2.

Figure 2. Standardized regression Coefficients (β) for the multiple mediation model. *p < .05; ***p < .001.

Table 3. Multiple mediation model of intolerance of uncertainty on fear of childbirth by positive beliefs about worry and avoidance of inner experiences.

Model	R^2	b	SE	β	p	CI (95%)
Model without mediator
IU → FOC(c)		1.05	0.15	0.34	<.001	0.75, 1.35
	0.12
Model with mediators
IU → Positive beliefs about worry (a1)		1.01	0.08	0.55	<.001	0.85, 1.18
IU → Avoidance of inner experiences (a2)		0.75	0.06	0.53	<.001	0.63, 0.88
Positive beliefs about worry → FOC (b1)		0.22	0.10	.014	<.05	0.03, 0.42
Avoidance of inner experiences → FOC (b2)		0.15	0.13	0.07	.24	−0.10 0.41
IU → FOC (c’)		0.71	0.20	.23	<.001	0.32, 1.09
	0.14
Indirect effects
Indirect effect of positive beliefs about worry (a1×b1)		0.23	0.11	0.07		0.01, 0.45
Indirect effect of avoidance of inner experiences (a2×b2)		0.11	0.10	0.04		−0.08, 0.33
Total indirect effect (a1×b1+a2×b2)		0.34	0.13	0.11		0.09, 0.61

95% CIs for the indirect effects obtained by bias-corrected bootstraps with 5000 resamples.

There was a significant indirect effect, excluding zero in the bootstrapped confidence interval, through positive beliefs about worry as a mediator (a1 × b1, β=.07, 95% BCI [0.01, 0.45]), but not through avoidance of inner experiences as a mediator (a2 × b2, β=.04, 95% BCI [–0.08, 0.33]). So, when combining both processes in the same model, positive beliefs about worry significantly partially mediated the relationship between IU and FOC while avoidance of inner experiences did not.

Discussion

In this study correlational analyses supported the proposed links between IU and FOC outlined in the IU-model. Higher ratings of FOC were associated with higher levels of IU, positive beliefs about worry, avoidance of inner experiences and negative problem orientation. When examining these relationships in a multiple regression model, negative problem orientation, positive beliefs about worry and avoidance of inner experiences, together explained about 12% of the variance in FOC. This suggests that the processes involved in the IU-model may assist in advancing our understanding of FOC. Yet, when including all three processes in the same model, negative problem orientation did not add significantly to the model, and was excluded from further analyses. It is possible that the association between negative problem orientation and FOC on the bivariate level can be accounted for by moderate correlations of negative problem orientation and the other two processes, potentially meaning that this process is less influential than the other two. Lastly, the exploration of potential mediators of the relation between IU and FOC showed that when combining the processes in the same model, positive beliefs about worry significantly partially mediated the relationship between IU and FOC while avoidance of inner experiences did not. This replicates and extends findings from earlier studies, where a link between positive beliefs about worry and FOC has also been found [13].

When interpreting the results, it needs to be considered that all analyses rely on cross-sectional data. Thus, no causal links should be inferred. Moreover, a convenience sample was used, which may imply doubts about whether the findings are directly generalizable to a clinical setting. This study focused on one single aspect of FOC, namely the role of IU. As there are other important factors, such as stress, depression, previous negative birth experiences or operative birth [7], it is not surprising that the multiple regression explained a fairly small amount of the total variance. It also needs to be kept in mind that the main criterion variable FOC relied on the two-item scale, which may imply a threat to the construct validity.

Our findings are well in line with the suggestion by Rondung and colleagues [10], that an exploration of transdiagnostic processes involved in worry and anxiety may advance the understanding of FOC. Although emerging evidence has suggested a link between IU and FOC [12,13] our results delineate the specific role of IU in FOC, and what psychological processes might be part of the association. The mediation analyses specifically pointed at positive beliefs about worry as a key mediating process.

This study adds to the theoretical understanding of FOC, by indicating that positive beliefs about worry, as part of intolerance of uncertainty, may be a potential process to target in the assessment and treatment of FOC.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data that support the findings of this study are available from the corresponding author, Ida Flink, upon reasonable request.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.