Abstract
Purpose
This study aimed to examine the effect of a pregnancy pillow used in the last trimester on fatigue and comfort in pregnant women.
Method
This study used an RCT design. The study was conducted with 77 primiparous pregnant women (39 intervention, 38 control) who met the inclusion criteria and were admitted to the obstetrics outpatient clinic of a university hospital in the Black Sea region. The pregnant women were randomly assigned to groups using “Random Allocation Software”. Data were collected through a Personal Information Form, the Chalder Fatigue Scale (CFS), and the Prenatal Comfort Scale (PCS). The Pearson chi-square test, Yates corrected chi-square test, Fisher’s Exact test, Fisher-Freeman-Halton test, Robust Mixed ANOVA, and partial eta-squared (η²) values were employed for effect size calculations and reported with 95% confidence intervals. The Phi coefficient (φ) and Cramer’s V were computed to measure the effect size for categorical analysis. The correlation coefficient (r) and Cohen’s d were employed to measure the effect size of both the Mann-Whitney U and Wilcoxon tests. In all analyses, the statistical significance level was considered to be p < 0.05.
Findings
In the intervention group, CFS scores significantly decreased from 19.38 ± 6.89 to 7.18 ± 5.21 and (p < 0.05), while PCS scores significantly increased from 53.21 ± 10.25 to 69.18 ± 6.19 a significant difference was found in the within-group comparison (p < 0.05). Conversely, in the control group, CFS scores significantly increased from 14.84 ± 6.25 to 28.84 ± 5.59 (p < 0.05), whereas PCS scores significantly decreased from 60.47 ± 12.28 to 40.58 ± 8.45 in the within-group comparison (p < 0.05). Robust regression analysis revealed that the post-test comfort score in the intervention group was 29.695 points higher than in the control group (p < 0.001). The post-test total fatigue score of the intervention group was 23.687 points less than that of the control group (p < 0.001).
Conclusion
The study findings indicated that using a pregnancy pillow during gestation enhanced comfort and decreased fatigue. Consequently, it can be stated that a pregnancy pillow may aid in preventing or alleviating fatigue during gestation.
Supplementary Information
The online version contains supplementary material available at https://doi.org/10.1186/s12884-026-09533-z.
Keywords: Comfort, Fatigue, Pregnancy pillow, Midwifery, Pregnancy
Introduction
Pregnancy involves numerous physiological, psychological, and emotional changes [1]. In addition to changes in the hormonal, cardiovascular, and urinary systems, pregnancy also brings about significant anatomical changes. These physiological and anatomical changes may contribute to fatigue in pregnant women. Fatigue is among the most common complaints reported by pregnant women [2, 3]. Fatigue in the first trimester is often attributed to increased oxygen consumption, elevated progesterone levels, and heightened metabolic demands. In the last trimester, the enlarging abdomen and uterine pressure on the diaphragm may hinder comfortable rest, contributing to increased fatigue [4, 5].
Research indicates that while fatigue is common among pregnant women, its intensity varies [2, 3, 6–8]. A study on perinatal maternal fatigue reported that 95% of pregnant women experienced fatigue [9]. Fatigue during pregnancy can negatively impact maternal well-being, adaptation to pregnancy, and mother-infant bonding [10, 11]. Studies examining prenatal and postpartum acute fatigue and factors associated with it reported that severe fatigue may increase the risk of preterm labor, operative vaginal delivery, cesarean section, and postpartum depression [6, 12].
Kolcaba and Dimarco define comfort as a state of well-being characterized by the absence of physical, mental, and social stress [13]. The physical, emotional, and physiological changes that occur during pregnancy can affect women’s comfort levels [14–17]. Therefore, reducing fatigue and increasing comfort during pregnancy is essential. Some data in the literature indicate that poor levels of comfort during pregnancy may lead to a decrease in APGAR score, low birth weight, and fetal death [14, 18]. Data also show that an increased level of comfort can facilitate mother-infant attachment and women’s adaptation to postpartum maternal roles, as well as protecting maternal and fetal health [15–17, 19].
In the last trimester of pregnancy in particular, physiological changes, such as changes in posture due to the growth of the abdomen and breasts, difficulty in breathing due to the pressure of the fetus on the diaphragm, and emotional and psychological changes due to the woman’s acquisition of a new role and responsibility, may give rise to fatigue and increasing discomfort in pregnant women [2, 3, 8, 20]. This situation has a significant impact on maternal and fetal health, mother-infant bonding, and the process of giving birth [2, 3, 8, 20]. When the relevant literature was examined, it was observed that studies often investigate the fatigue levels of pregnant women in different trimesters [2, 3, 7, 8, 20]. Although it is known that fatigue is a common problem during pregnancy and causes a deterioration in comfort levels, there is a lack of effective interventions to combat fatigue and improve comfort [3]. These two issues are commonly reported in the third trimester of pregnancy, and traditional interventions include pharmaceutical treatments or recommendations addressing general sleep hygiene. Evidence from high-quality randomized controlled trials assessing structured positioning support devices, such as pregnancy pillows, is rare. Moreover, prior research has predominantly focused on sleep quality or pain outcomes. Fatigue and comfort, two clinically significant and functionally pertinent variables, are infrequently evaluated concurrently in a randomized controlled design. Consequently, this study aimed to evaluate the impact of using a pregnancy pillow during the last trimester on fatigue and comfort in pregnant women.
Hypotheses
H0: Pregnant women who use a pregnancy pillow during the last trimester will have higher fatigue scores and lower prenatal comfort scores than those receiving routine care.
H1: Pregnant women who use a pregnancy pillow during the last trimester will have lower fatigue scores and higher prenatal comfort scores than those receiving routine care.
Methods
Study design, participants, and randomization
This study had a randomized controlled experimental design. The trial protocol was registered (Registration Date: 12.28.2023/ NCT06200428). The study was conducted with pregnant women who attended the obstetrics outpatient clinic of a university hospital between December 2023 and March 2024. The population of the study consisted of primiparous pregnant women who attended this clinic between the specified dates. Based on a priori power analysis using PCS final test scores from the study by Ibici et al. [21], the minimum sample size required to achieve 80% power at an alpha level of 0.05 was determined to be 70 pregnant women (35 per group). A total of 77 pregnant women (39 intervention, 38 control) were enrolled in the study. Pregnant women with conditions such as sleep disturbances, preeclampsia, or gestational diabetes, as well as those who withdrew from the study, were excluded. Post-hoc power analysis conducted upon the completion of the study revealed that the study achieved a power exceeding 99.9% at an alpha level of 0.05 with an effect size of d = 3.86.
Pregnant women who were older than 18 years old, at 29–30 weeks of gestation, had not been diagnosed with any health problems in screening tests and pregnancy follow-ups, did not smoke or drink alcohol, and did not have any physiological or psychological disorders were included in the study. Pregnant women who did not wish to continue participating, those at risk of developing preeclampsia, those experiencing sleep disorders, those who did not fully answer the questions, and those who could not use the pillow effectively were excluded.
Randomization
Randomization was achieved using a simple random assignment technique. Pregnant women meeting the inclusion criteria were randomly assigned to groups by researcher BUÖ using Random Allocation Software. In accordance with the research objectives, participant blinding was achieved by keeping the participants unaware of their assigned group. The interventions were conducted by BUÖ, while data were collected by ÖA, who was oblivious to the identities of the intervention and control groups, hence assuring data collector blinding. The dataset was presented to an independent statistician in a format where groups were identified only by codes (e.g., Group A/B), and the blinding of statisticians was achieved by keeping the group assignments confidential until the analysis was complete. Consequently, this randomized controlled trial employed a triple-blind design. The research results were assessed by SÖA and HÖ. To mitigate potential data loss and preserve the integrity of the randomization, a greater number of participants than the originally specified sample size was incorporated into the study.
Data collection tools
Personal information form
This form, which was created by the researchers after reviewing the literature, consisted of questions about the age, marital status, education, and employment status of the pregnant women, the age and educational status of their spouses, their family structure, and their economic status.
Chalder Fatigue Scale (CFS)
This scale, developed in 1993, assesses the fatigue felt by an individual in the last month through self-report [22]. The scale was revised in 2010 and three items were removed [23]. The validity and reliability study of the Turkish version of the scale was conducted by Adın et al. [24]. The scale consists of a total of 11 items and two sub-dimensions (“physical fatigue” and “mental fatigue”). The score obtained from the scale ranges between 0 and 33 points. An increase in the score obtained indicates an increase in the severity of fatigue. The Cronbach’s alpha reliability coefficient of the Turkish version of the scale was 0.90 [24]. In the present study, the Cronbach’s alpha reliability coefficient of the scale was found to be 0.88.
Prenatal Comfort Scale (PCS)
This scale for determining prenatal comfort was developed in Japan in 2011 by Takeishi et al. [25]. The Turkish validity and reliability study was conducted by Kaya Şenol et al. [26]. The first version of the scale had 34 items; however, this was later revised down by the authors to 15 items [19]. The scale consists of five sub-dimensions (“The effect of improving relations with the spouse on the fatherhood role”, “Interacting with the movements of the fetus”, “Social support received from people in the immediate environment”, “Acceptance of the maternal role and attachment to the baby”, “Recognizing changes in oneself during pregnancy”) [19]. The score obtained from the scale ranges between 0 and 75 points. A higher score on the scale indicates an increased level of comfort [19, 25]. The Cronbach’s alpha reliability coefficient of the Turkish version of the scale was 0.82 [24]. In the present study, the Cronbach’s alpha reliability coefficient of the scale was found to be 0.87.
Data collection procedures
The study was conducted with pregnant women who attended the obstetrics outpatient clinic of a university hospital between December 2023 and March 2024. The participants in the intervention and control groups were pregnant women who met the inclusion criteria and who visited the hospital for follow-up. These women were also asked to record their sleep duration in a sleep diary. Data was collected during home visits in the 4th and 8th weeks.
Intervention group
A pregnancy pillow is a multi-zone positional support device designed to reduce the musculoskeletal discomfort associated with increased biomechanical loading and postural changes, particularly during the third trimester of pregnancy. Increased abdominal volume and changes in the center of gravity are associated with increased lumbar lordosis and pelvic pressure, which can lead to pain, muscle fatigue, and reduced comfort. A pregnancy pillow aims to optimize spinal alignment, reduce mechanical stress, and maintain proper lateral positioning by providing simultaneous support to the cervical, abdominal, lumbar, and lower extremity regions. The pillowcases used in the study were made of 100% cotton poplin fabric, characterized by its breathability, hypoallergenic properties, and resistance to perspiration. The pregnancy pillow used had a beaded fiber filling, allowing it to recover its shape and resist flattening, as well as preventing it from felting. The zippered cover of the pillow made the inside easier to remove, launder, and reattach (Fig. 1). Participants using the pregnancy pillow were advised to sleep on their left side and were informed that they could use the pillow at any time, day or night. No further intervention was made on the groups. No allergic reactions were reported. Pregnancy pillows are typically considered a low-risk, non-invasive intervention. No adverse events or clinically significant discomfort associated with the use of the pregnancy pillow were reported by the trial subjects. Specifically, there were no reports of complaints such as musculoskeletal pain, restricted movement during sleep, overheating, or increased nighttime discomfort.
Fig. 1.
Images from the intervention group
The current literature states that the optimal sleep duration should be individualized, that there is no ideal sleep duration valid for everyone, and that the amount of sleep needed is affected by individual differences, and environmental, physiological and psychological factors [27–29]. On the other hand, it has been reported that pregnant women with poor sleep quality and fatigue during pregnancy are usually those who have less than 5 h sleep a night [30–33]. For this reason, when the intervention group was informed about the use of the maternity pillow they were also told that they should sleep with it for at least 6 h a night (Fig. 1). The women were followed up in the fourth and eighth weeks after sleeping with the pillow. As a result of the follow-ups, it was determined that all the pregnant women included in the study had slept with the pillow for at least 6 h a night (Fig. 2). Seven participants in the intervention group were excluded: two reported sleep disorders, three opted out, one experienced a preterm birth, and one was unable to use the pillow. The study was finalized with 39 participants. Before the commencement of the research, the participants underwent a comprehensive training on keeping a sleep diary, understanding the features of the pillow, and the duration and manner of sleeping with the pillow. Their questions regarding the trial were also fully addressed.
Fig. 2.
CONSORT study flow diagram
Control group
Routine care was provided to the pregnant women in the control group during the study. The first follow-up was performed at the first interview, followed by the second and third follow-ups in the fourth and eighth weeks. After the last follow-up was completed, the 39 pregnant women in the control group were given a pregnancy pillow to ensure they had the opportunity to use it (Fig. 2) [34–36]. Nine participants in the control group were excluded: two were diagnosed with preeclampsia, one experienced gestational diabetes, one opted out, and one experienced a preterm birth. The study was finalized with 38 participants.
Data analysis
Statistical analyses were performed using the IBM SPSS Statistics Version 23 and the R Project for Statistical Computing program. Both the Shapiro-Wilk and Kolmogorov-Smirnov tests were used for assessing whether the dataset followed a normal distribution. Non-normally distributed data were presented in median (Q1-Q3), whereas trimmed mean + SE was used for robust analyses to handle outliers. Categorical data were expressed as frequency and percentage (%). When comparing two independent groups, the Mann-Whitney U test was used for non-normally distributed data. The Pearson Chi-square test, Yates corrected Chi-square test, Fisher’s Exact test, and the Fisher-Freeman-Halton test were used to compare categorical variables across groups. The Wilcoxon signed-rank test was applied to compare paired measurements. Robust Mixed ANOVA was used for non-normally distributed data in the analysis of repeated measures by group and time. Group effect, time effect, and group×time interactions were evaluated in the models. Multiple comparison tests (MCTs) combining the Robust t-test with Holm correction were used to assess significant interactions and main effects. Effect sizes were calculated using partial eta-squared (η²) values and reported with 95% confidence intervals. For categorical analyses, the Phi coefficient (φ) and Cramer’s V were calculated. In the Mann-Whitney U and Wilcoxon tests, effect size was assessed using the correlation coefficient (r) and Cohen’s d. In all analyses, the statistical significance level was set at p < 0.05.
Findings
Table 1 shows that there was no statistically significant difference between the intervention and control groups in terms of sociodemographic characteristics (p > 0.05). The low effect sizes further corroborate that there was no substantial imbalance between the groups, indicating that the randomization was effective.
Table 1.
Comparison of socio-demographic characteristics of the pregnant women in the intervention and control groups
| Intervention | Control | Total | Test statistics | p | ES (95% CI) | |
|---|---|---|---|---|---|---|
| Age | 24 (22: 33) | 28 (25: 32) | 27 (23: 33) | 596.000 | 0.139a | 0.342 [-0.110: 0.791]* |
| Spouse’s Age | 33 (28: 38) | 33 (28: 38) | 31 (28: 37) | 688.000 | 0.588a | 0.123 [-0.324: 0.570]* |
| Place of Residence | ||||||
| Province | 36 (92.3) | 34 (89.5) | 70 (90.9) | --- | 0.711d | 0.049 [0.000: 0.169]** |
| Town | 3 (7.7) | 4 (10.5) | 7 (9.1) | |||
| Educational Status | ||||||
| Primary school | 4 (10.3) | 6 (15.8) | 10 (13) | 1.685 | 0.650e | 0.145 [0.009: 0.231]*** |
| Middle school | 5 (12.8) | 6 (15.8) | 11 (14.3) | |||
| High school | 23 (59) | 17 (44.7) | 40 (51.9) | |||
| Undergraduate and postgraduate | 7 (17.9) | 9 (23.7) | 16 (20.8) | |||
| Employment Status | ||||||
| Employed | 16 (41) | 13 (34.2) | 29 (37.7) | 0.146 | 0.703c | 0.070 [0.001: 0.234]** |
| Unemployed | 23 (59) | 25 (65.8) | 48 (62.3) | |||
| Spouse’s Educational Status | ||||||
| Primary school | 2 (5.1) | 5 (13.2) | 7 (9.1) | 2.801 | 0.420e | 0.193 [0.086: 0.438]*** |
| Middle school | 4 (10.3) | 5 (13.2) | 9 (11.7) | |||
| High school | 22 (56.4) | 22 (57.9) | 44 (57.1) | |||
| Undergraduate and postgraduate | 11 (28.2) | 6 (15.8) | 17 (22.1) | |||
| Family Structure | ||||||
| Nuclear family | 34 (87.2) | 29 (76.3) | 63 (81.8) | 0.884 | 0.347c | 0.141 [0.005: 0.340]** |
| Extended family | 5 (12.8) | 9 (23.7) | 14 (18.2) | |||
| Economic Status | ||||||
| Income less than expenses | 11 (28.2) | 10 (26.3) | 21 (27.3) | 0.322 | 0.851b | 0.065 [0.005: 0.117]*** |
| Income equal to expenses | 14 (35.9) | 16 (42.1) | 30 (39) | |||
| Income more than expenses | 14 (35.9) | 12 (31.6) | 26 (33.8) | |||
ES Effect size; aMann-Whitney U test, bChi-square test, cYates correction, dFisher’s Exact test, eFisher-Freeman-Halton test, frequency (percent), median (Q1-Q3); **Phi Coefficient (φ) and ***Cramer’s V (V); 95% confidence interval was calculated using the bootstrap method; *Cohen’s d(d)
Table 2 presents the average nighttime sleep duration for the women when using a pregnancy pillow. A statistically significant increase in average nighttime sleep duration was observed when comparing the second and third trimesters (p = 0.001). The calculated effect size indicates that the intervention had a moderate effect on sleep duration.
Table 2.
Average sleep duration per night of pregnant women using a pregnancy pillow
| Median (Q1-Q3) | Test Statistics* | p | ES [95% CI] | |
|---|---|---|---|---|
| Second follow-up: duration of sleep with maternity pillow (hours) | 6 (5: 7) | -3.446 | 0.001 | 0.378 [0.071: 0.620] |
| Third follow-up: duration of sleep with maternity pillow (hours) | 7 (6: 8) |
ES [95% CI]= Effect Size [95% Confidence Interval]: Paired Correlation (r); *Wilcoxon test
Table 3 shows that the group × time interaction was statistically significant in terms of physical fatigue, mental fatigue, and total fatigue scores (p < 0.001). It is noteworthy that fatigue scores decreased regularly over time in the intervention group, while they increased in the control group. The high effect sizes of the group × time interaction (ES = 0.610–0.730) suggest that the intervention had a significant effect on fatigue levels.
Table 4.
P-values of the multiple comparison test results of the intervention and control groups
| Group*time interaction | Physical Fatigue | Mental Fatigue | Total Fatigue |
|---|---|---|---|
| Intervention first follow-up – Intervention second follow-up | < 0.001 | 0.002 | < 0.001 |
| Intervention first follow-up – Intervention third follow-up | < 0.001 | < 0.001 | < 0.001 |
| Intervention first follow-up – Control first follow-up | 0.003 | 0.063 | 0.006 |
| Intervention first follow-up – Control second follow-up | 0.071 | 0.244 | 0.094 |
| Intervention first follow-up – Control third follow-up | < 0.001 | < 0.001 | < 0.001 |
| Intervention second follow-up – Intervention third follow-up | < 0.001 | 0.003 | < 0.001 |
| Intervention second follow-up – Control first follow-up | 0.013 | 0.244 | 0.042 |
| Intervention second follow-up – Control second follow-up | < 0.001 | < 0.001 | < 0.001 |
| Intervention second follow-up – Control third follow-up | < 0.001 | < 0.001 | < 0.001 |
| Intervention third follow-up – Control first follow-up | < 0.001 | < 0.001 | < 0.001 |
| Intervention third follow-up – Control second follow-up | < 0.001 | < 0.001 | < 0.001 |
| Intervention third follow-up – Control third follow-up | < 0.001 | < 0.001 | < 0.001 |
| Control first follow-up – Control second follow-up | < 0.001 | 0.002 | < 0.001 |
| Control first follow-up – Control third follow-up | < 0.001 | < 0.001 | < 0.001 |
| Control second follow-up – Control third follow-up | < 0.001 | 0.001 | < 0.001 |
Robust t-test with Holm Correction
Table 3.
Intragroup and intergroup comparison of total and subscale scores of CFS
| Time | Group | Total | Test statistics | p X | ES (95% CI) | ||
|---|---|---|---|---|---|---|---|
| Intervention | Control | ||||||
| Physical Fatigue | |||||||
| First follow-up | 12.62 ± 0.78a | 9.17 ± 0.73b | 10.87 ± 0.58 | Group | 118.871 | < 0.001 | 0.670 (0.529: 0.761) |
| Second follow -up | 6.92 ± 0.41c | 14.50 ± 0.75a | 10.68 ± 0.65 | Time | 1.914 | 0.156 | 0.058 (0.000: 0.186) |
| Third follow-up | 3.68 ± 0.65d | 19.47 ± 0.69e | 11.49 ± 1.09 | Group* Time | 83.435 | < 0.001 | 0.730 (0.611: 0.803) |
| Total | 7.62 ± 0.52 | 14.46 ± 0.58 | |||||
| Mental Fatigue | |||||||
| First follow-up | 6.84 ± 0.46ab | 5.44 ± 0.41ac | 6.13 ± 0.33 | Group | 57.055 | < 0.001 | 0.463 (0.289: 0.596) |
| Second follow-up | 4.76 ± 0.33c | 7.56 ± 0.44b | 6.11 ± 0.33 | Time | 0.71 | 0.496 | 0.022 (0.000: 0.116) |
| Third follow-up | 3.27 ± 0.30d | 9.72 ± 0.37e | 6.44 ± 0.47 | Group* Time | 49.373 | < 0.001 | 0.610 (0.453: 0.712) |
| Total | 4.85 ± 0.24 | 7.63 ± 0.29 | 6.21 ± 0.22 | ||||
| Total Fatigue | |||||||
| First follow-up | 19.46 ± 1.15a | 14.61 ± 1.10d | 17.00 ± 0.85 | Group | 105.936 | < 0.001 | 0.636 (0.487: 0.734) |
| Second follow-up | 11.68 ± 0.69b | 22.06 ± 1.12a | 16.76 ± 0.92 | Time | 1.47 | 0.238 | 0.045 (0.000: 0.163) |
| Third follow-up | 6.92 ± 0.89c | 29.19 ± 1.01e | 17.90 ± 1.54 | Group* Time | 77.831 | < 0.001 | 0.714 (0.590: 0.791) |
| Total | 12.50 ± 0.76 | 22.06 ± 0.85 | |||||
XRobust Mixed ANOVA; Trimmed mean ±Standard Error; a-e: There is no difference between interactions denoting the same letter; ES [95% CI]: Partial eta squared effect size 95% confidence interval
The multiple comparison test results presented in Table 4 show statistically significant changes in the levels of physical, mental, and total fatigue in the intervention group from the first follow-up to the second and third follow-ups (p < 0.05). The significant difference in the intervention group, particularly in the third follow-up measurements, when compared to the second and third follow-up measurements of the control group, supports the assumption that the intervention was effective in reducing fatigue. Significant changes were also observed in the control group’s comparisons over time, and the direction of change, when evaluated together with the mean scores in Table 3a, indicated an increase in fatigue levels.
Table 5 shows that the group × time interaction was statistically significant for all sub-dimensions of the PCS and the total comfort score (p < 0.001). It is noteworthy that the comfort scores increased over time in the intervention group, while decreasing in the control group. The intervention group, particularly in the total comfort score, scored higher at the third follow-up compared to the control group, and the high effect size (ES = 0.701) suggests that the intervention had a significant effect on prenatal comfort.
Table 5.
Intragroup and intergroup comparison of overall and subscale scores of PCS
| Time | Group | Total | Test statistics | p X | ES (95% CI) | ||
|---|---|---|---|---|---|---|---|
| Intervention | Control | ||||||
| The effect of improving relations with the spouse on the fatherhood role | |||||||
| First follow-up | 14.46 ± 0.53a | 17.00 ± 0.64b | 15.79 ± 0.41 | Group | 30.111 | < 0.001 | 0.306 (0.138: 0.461) |
| Second follow-up | 17.24 ± 0.42b | 14.89 ± 0.46a | 16.08 ± 0.34 | Time | 1.755 | 0.182 | 0.055 (0.000: 0.181) |
| Third follow-up | 18.95 ± 0.25c | 11.86 ± 0.48d | 15.58 ± 0.52 | Group * Time | 51.981 | < 0.001 | 0.631 (0.477: 0.730) |
| Total | 16.94 ± 0.30 | 14.65 ± 0.36 | |||||
| Interacting with the movements of the fetus | |||||||
| First follow-up | 7.54 ± 0.32ab | 8.33 ± 0.32ac | 7.96 ± 0.23 | Group | 41.042 | < 0.001 | 0.378 (0.204: 0.525) |
| Second follow-up | 8.86 ± 0.17c | 7.33 ± 0.23b | 8.14 ± 0.17 | Time | 0.285 | 0.753 | 0.009 (0.000: 0.079) |
| Third follow-up | 9.84 ± 0.10d | 6.28 ± 0.24e | 8.17 ± 0.26 | Group * Time | 45.102 | < 0.001 | 0.596 (0.432: 0.702) |
| Total | 8.84 ± 0.15 | 7.35 ± 0.18 | |||||
| Social support received from people in the immediate environment | |||||||
| First follow-up | 11.49 ± 0.50a | 12.03 ± 0.51ac | 11.79 ± 0.35 | Group | 32.061 | < 0.001 | 0.353 (0.167: 0.512) |
| Second follow-up | 13.08 ± 0.31bc | 10.58 ± 0.54a | 12.01 ± 0.29 | Time | 3.913 | 0.025 | 0.115 (0.000: 0.266) |
| Third follow-up | 14.05 ± 0.26b | 7.89 ± 0.55d | 11.18 ± 0.49 | Group * Time | 36.240 | < 0.001 | 0.546 (0.369: 0.664) |
| Total | 12.97 ± 0.22 | 10.23 ± 0.35 | |||||
| Acceptance of the maternal role and attachment to the baby | |||||||
| First follow-up | 10.86 ± 0.38a | 12.94 ± 0.38bc | 11.90 ± 0.30 | Group | 19.205 | < 0.001 | 0.220 (0.071: 0.380) |
| Second follow-up | 12.95 ± 0.27b | 11.39 ± 0.34a | 12.18 ± 0.24 | Time | 1.397 | 0.255 | 0.043 (0.000: 0.158) |
| Third follow-up | 14.00 ± 0.25c | 9.53 ± 0.29d | 11.82 ± 0.34 | Group* Time | 61.094 | < 0.001 | 0.661 (0.519: 0.751) |
| Total | 12.64 ± 0.22 | 11.30 ± 0.23 | |||||
| Recognizing changes in oneself during pregnancy | |||||||
| First follow-up | 9.00 ± 0.46ab | 10.94 ± 0.69ac | 9.99 ± 0.42 | Group | 67.119 | < 0.001 | 0.488 (0.323: 0.613) |
| Second follow-up | 12.32 ± 0.37c | 7.61 ± 0.53b | 10.03 ± 0.44 | Time | 4.354 | 0.017 | 0.131 (0.004: 0.289) |
| Third follow-up | 12.89 ± 0.49c | 4.86 ± 0.44d | 8.92 ± 0.60 | Group* Time | 49.928 | < 0.001 | 0.634 (0.476: 0.734) |
| Total | 11.48 ± 0.30 | 7.73 ± 0.42 | |||||
| Total Comfort Score | |||||||
| First follow-up | 53.30 ± 1.66a | 60.89 ± 2.17b | 57.10 ± 1.43 | Group | 61.800 | < 0.001 | 0.498 (0.322: 0.627) |
| Second follow-up | 64.16 ± 1.31b | 51.67 ± 1.57a | 58.21 ± 1.28 | Time | 3.334 | 0.042 | 0.097 (0.000: 0.241) |
| Third follow-up | 69.62 ± 0.94c | 40.36 ± 1.51d | 55.32 ± 2.05 | Group*Time | 72.446 | < 0.001 | 0.701 (0.571: 0.781) |
| Total | 62.65 ± 1.03 | 50.83 ± 1.35 | |||||
XRobust Mixed ANOVA; Trimmed mean ±Standard Error; a-e: There is no difference between interactions denoting the same letter; ES [95% CI]: Partial eta squared effect size 95% confidence interval
The results of the multiple comparison test in Table 6 show that there were statistically significant improvements in the sub-dimensions of the PCS in the intervention group from the first follow-up to the third follow-up (p < 0.05). Furthermore, the significant difference in the intervention group’s scores compared to the control group, particularly in the third follow-up measurements, supports the ideas that the intervention had a positive effect on prenatal comfort.
Table 6.
P-values of the Multiple Comparison Test Results
| Group*time interaction | The effect of improving relations with the spouse on the fatherhood role | Interacting with the movements of the fetus | Social support received from people in the immediate environment | Acceptance of the maternal role and attachment to the baby | Recognizing changes in oneself during pregnancy | Total Comfort Score |
|---|---|---|---|---|---|---|
| Intervention first follow-up – Intervention second follow-up | < 0.001 | 0.002 | 0.034 | < 0.001 | < 0.001 | < 0.001 |
| Intervention first follow-up – Intervention third follow-up | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 |
| Intervention first follow-up – Control first follow-up | 0.010 | 0.201 | 0.425 | < 0.001 | 0.076 | 0.014 |
| Intervention first follow-up – Control second follow-up | 0.739 | 0.581 | 0.399 | 0.566 | 0.121 | 0.455 |
| Intervention first follow-up – Control third follow-up | 0.002 | 0.008 | < 0.001 | 0.019 | < 0.001 | < 0.001 |
| Intervention second follow-up – Intervention third follow-up | 0.003 | < 0.001 | 0.065 | 0.019 | 0.335 | 0.003 |
| Intervention second follow-up – Control first follow-up | 0.739 | 0.253 | 0.202 | 0.997 | 0.139 | 0.358 |
| Intervention second follow-up – Control second follow-up | 0.001 | < 0.001 | < 0.001 | 0.002 | < 0.001 | < 0.001 |
| Intervention second follow-up – Control third follow-up | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 |
| Intervention third follow-up – Control first follow-up | 0.019 | < 0.001 | 0.003 | 0.052 | 0.076 | 0.002 |
| Intervention third follow-up – Control second Follow-up | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 |
| Intervention third follow-up – Control third follow-up | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 |
| Control first follow-up – Control second follow-up | 0.019 | 0.040 | 0.178 | 0.011 | < 0.001 | 0.003 |
| Control first follow-up – Control third follow-up | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 | < 0.001 |
| Control second follow-up – Control third follow-up | < 0.001 | 0.008 | 0.003 | < 0.001 | < 0.001 | < 0.001 |
Robust t-test with Holm Correction
Discussion
Pregnancy-related changes can reduce the comfort levels of pregnant women and cause fatigue [37]. Such fatigue is known to increase the risk of preterm birth, dystocia, operative vaginal delivery, cesarean section, and postpartum depression [12, 38]. The negative effects of fatigue and its relationship with trimesters have been discussed extensively in the literature. However, no systematic interventions have been made or studied [2, 3, 6, 7, 11, 12]. This study thus aimed to examine the effect of a pregnancy pillow used in the last trimester on fatigue and comfort in pregnant women. The results obtained are discussed here in relation to other findings in the relevant literature.
Fatigue is one of the complaints most commonly and consistently reported by pregnant women [2]. A study aiming to determine the severity of fatigue experienced by pregnant women in different trimesters of pregnancy demonstrated that more than 90% of pregnant women in the first, second, and third trimesters were affected by fatigue. Furthermore, pregnant women in the third trimester were observed to have higher fatigue scores [2]. Despite extensive research on fatigue during pregnancy [39–41], investigations into systematic therapies aimed at preventing or alleviating its effects remain scarce [3, 8, 20]. One of these studies sought to assess the efficacy of progressive muscle relaxation exercises and aromatherapy in alleviating fatigue symptoms of pregnant women. This quasi-experimental study demonstrated that a combination of progressive muscle relaxation exercises and aromatherapy effectively reduced the fatigue levels of pregnant women [20]. The current study demonstrated that using a pregnancy pillow effectively reduced fatigue and thus represents a practical, safe, and non-invasive method for enhancing comfort during pregnancy.
Among the main underlying causes of fatigue are sleep disorders. Research indicates a substantial correlation between sleep quality and fatigue levels in pregnant women, with sleep quality declining as fatigue intensifies [2, 7, 42–44]. In a randomized controlled trial in which a pregnancy pillow was used as the intervention, it was reported that sleep quality improved in the last trimester of pregnancy [45]. This finding may serve as a potential explanation for the decrease in fatigue levels demonstrated in this study. The improved sleep quality attributed to the support offered by the pregnancy pillow in the sleeping posture may have contributed to the decrease in physical, mental, and overall fatigue levels.
Comfort is a fundamental element of the care provided throughout pregnancy and labor [46]. In a randomized controlled trial examining the relationship between pregnancy pillows and prenatal comfort, it was found that using a pregnancy pillow in the third trimester increased comfort in the intervention group [45]. Similarly, women in the intervention group of the current study who used pregnancy pillows reported higher comfort levels and less fatigue compared to those in the control group. Increasing the comfort of pregnant women through the use of pregnancy pillows may have led them to feel less tired.
Studies of interventions aimed at improving the comfort of pregnant women have reported various results [21, 47]. For example, in a randomized controlled trial examining the effect of listening to music on sleep quality and comfort in pregnant women, it was concluded that listening to music did not significantly affect comfort levels, while mindfulness-based stress reduction programs were shown to improve prenatal comfort [21, 47]. The disparities may be attributed to the complex physiological and psychological alterations that arise during pregnancy. Specifically, postural alterations resulting from abdominal expansion and heightened biomechanical load can adversely impact rest, sleep, and physical comfort. Thus, it can be argued that pregnancy pillows help alleviate musculoskeletal problems by promoting proper body alignment, improving sleep quality, and consequently increasing the comfort of pregnant women. It was concluded in this study that the women in the intervention group who used pregnancy pillows experienced higher level of comfort and lower fatigue levels. The physical support and increased comfort offered by the pregnancy pillows may have facilitated the decrease that they experienced in their fatigue.
The results of this randomized controlled trial revealed that using a pregnancy pillow in the last trimester of pregnancy is an effective alternative method to reduce the fatigue caused by pregnancy-related changes and to increase the comfort of pregnant women. The use of a pregnancy pillow has no known side effects on maternal or fetal health and is a cost-effective and easy-to-apply method.
Generalizability and limitations
Other factors that may have positively or negatively affected the fatigue and comfort levels of the pregnant women included in the study (such as socio-demographic characteristics, family background, relationship with the spouse, and general stress) could not be controlled. This is one limitation of the study. Another limitation of the study is that the follow-up assessments were conducted at weeks 4 and 8. Studies with longer follow-up periods are recommended in order to evaluate the lasting effects of the intervention implemented. Including participants from various gestational periods (e.g., early pregnancy and postpartum stages) would provide a more comprehensive understanding of fatigue and comfort throughout pregnancy. The study was restricted to pregnant women who attended one hospital in the relevant province and the result can thus only be generalized to those pregnant women who participated in the study. Given that data collection was limited to a single hospital setting, the generalizability of the findings to the broader population is restricted. Further limitations of the study include the self-reported nature of the research, potential compliance/reporting bias regarding the use of the pregnancy pillow, and the absence of a placebo group. Consequently, replication of this study across diverse population groups and multiple healthcare settings with placebo groups is recommended to enhance external validity.
Conclusion
In this study, which was conducted to examine the effect of a pregnancy pillow used in the last trimester on fatigue and comfort, it was determined that using the pillow increased the comfort levels of pregnant women and reduced their fatigue. A pregnancy pillow can be used to prevent or reduce the effect of fatigue that occurs for various reasons during pregnancy. It is recommended that randomized controlled trials be conducted to examine the relationship between pillow use and sleep quality. Future studies may also be conducted to address the following research gaps: the association between pregnancy pillow use and sleep quality; the effects of various pillow types on sleep parameters, fatigue levels, and maternal comfort; the impact of socio-demographic factors on comfort and fatigue outcomes; and the potential effects of pregnancy pillow usage on fetal well-being and development.
On the basis of this study’s findings, it is anticipated that the use of a pregnancy pillow may enhance comfort and reduce discomfort, potentially leading to improvements in the quality of life of pregnant women. It is suggested that pregnant women could use such pillows to increase their comfort and alleviate discomfort in clinical settings and prenatal education classes. Furthermore, it is recommended that the use of pregnancy pillows be incorporated into prenatal education curricula. Given the potential for improving maternal comfort and reduce pregnancy-related discomfort, it would be advisable to integrate pregnancy pillows into midwifery care practices.
Supplementary Information
Acknowledgements
This paper was presented orally at the 12th International Scientific Research and Innovation Congress in Al Farabi on 3–4 March 2024 in Almaty, Kazakhstan.
Authors’ contributions
SÖA: Conceptualization, İnvestigation, Formal Analysis, Writing-original draft, Writing-review & editing, Methodology, BUÖ : Conceptualization, Formal Analysis, Methodology, Editing, ÖA : Conceptualization, Formal Analysis, Methodology, Editing HÖ: Conceptualization, Methodology, Editing.
Funding
No funding was received for this article.
Data availability
The corresponding author, upon reasonable request, will provide data supporting the findings of this study.
Declarations
Ethics approval and consent to participate
Before starting the study, ethics committee approval (Amasya University Non-Interventional Clinical Research Ethics Committee: E-76988455-050.01.04-169493) and the necessary permissions to conduct the study were obtained. Since the individual rights of the participants needed to be protected during the study, the Helsinki Declaration on Human Rights was adhered to throughout. The participants were informed in detail about the study’s procedures, and their written and verbal consent was obtained.
Consent for publication
Not applicable.
Competing interests
The authors declare no competing interests.
Footnotes
This study was presented orally at the 12th International Scientific Research and Innovation Congress, 3-4 March 2024, in Almaty, Kazakhstan.
Publisher’s note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
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Associated Data
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Supplementary Materials
Data Availability Statement
The corresponding author, upon reasonable request, will provide data supporting the findings of this study.