Effectiveness of nonpharmacological interventions for reducing postpartum fatigue: A systematic review and meta- analysis


 Background: Postpartum fatigue is the most common issue among postnatal women and it could not only seriously affect the health of mothers but also bring about adverse impacts on their offspring. However, postpartum fatigue is an ongoing research issue but is seldom treated. This systematic review and meta-analysis aims to synthesize nonpharmacological evidence and evaluate the effectiveness of interventions for reducing postpartum fatigue among puerperae.Methods: The Cochrane Library, PubMed, Embase, Web of Science, PsycINFO, CINAHL and ProQuest databases were searched for papers published from inception until February 2021. Grey literature was searched using OpenGrey. Randomized controlled trials (RCTs) or controlled clinical trials (CCTs) evaluating nonpharmacological interventions for postpartum fatigue reduction were eligible for inclusion. The methodological quality of the included studies was independently assessed by two reviewers using the Cochrane risk-of-bias tool and the risk of bias in nonrandomized studies of interventions. The meta-analysis was conducted using Review Manager 5.3.Results: Seventeen published clinical trials matched the eligibility criteria for the systematic review, and thirteen studies involving 1686 participants were included in this meta-analysis. The results of the meta-analysis revealed that exercise (SMD= -1.74, 95% CI=-2.61 to -0.88), physical therapy (SMD= -0.50, 95% CI=-0.96 to -0.03) and drinking tea (MD= -3.12, 95% CI=-5.44 to -0.80) resulted in significant improvements in women’s postpartum fatigue at postintervention. Drinking tea may have beneficial effects on depression (MD= -2.89, 95% CI=-4.30 to -1.49). Positive effects of psychoeducational interventions on postpartum fatigue or depression were not observed.Conclusions: This review provides evidence that exercise, physical therapy and drinking tea are effective nonpharmacological interventions for relieving postpartum fatigue. Detailed instructions for postpartum exercise should be offered to puerperae. Physical therapy could be used in combination to enhance the intervention efficacy. Multiple daily cups of tea may be recommended. Psychoeducational interventions were ineffective for postpartum fatigue, but they could be integrated with the internet or smartphones to improve their effectiveness in the future. Fatigue-related nonpharmacological interventions of psychological outcomes still need to be studied.


Background
Postpartum fatigue is considered the most common issue that postnatal women confront when they transition to motherhood [1]. Postpartum fatigue is described as feelings of suffocation, exhaustion, and decreases in physical and mental capacity [2]. These symptoms may disturb approximately 64% of mothers in their postpartum stage [1]. It was reported that 38.8%, 27.1% and 11.4% of women perceived fatigue at 10 days, 1 month and 3 months after delivery, respectively, which indicates that the in uence of postpartum fatigue on puerperae is general and persistent. Negative psychological symptoms (e.g., depression, anxiety and stress), sleep problems and less effective parenting behaviours are closely associated with the severity of postpartum fatigue [3][4][5]. Importantly, previous research demonstrated that postpartum fatigue could not only seriously affect the maternal health of mothers but also bring about adverse impacts on their offspring [6]. Experiences of fatigue could negatively affect breastmilk production, maternal-infant attachment and interactions [2,5,7], thereby delaying the development of babies [8].
Hence, it is signi cant to deliberately avert and relieve fatigue during the postpartum period via healthy and effective approaches. In fact, interventions for reducing postpartum fatigue have particular advantages. They are not only important to puerperae' physical relief but also have potential bene ts on the improvement of maternal mental health. Cindy-Lee et al. [9] suggested that preventing postpartum depression could start from the perspective of fatigue management. Compared with recommended psychotherapy, fatigue management is less stigmatising and may be an acceptable rst step for women to seek assistance and receive treatment for psychological issues [9]. However, postpartum fatigue is an ongoing research issue but is seldom treated. On the positive side, there is rapidly growing interest in this area. Although studies of nonpharmacological interventions conducted in puerperae with the aim of reducing fatigue are accumulating, different interventions may lead to varied effects [10][11][12][13]. Previous relevant systematic reviews and meta-analyses have clari ed the positive relationship of postpartum fatigue and depression [3], the predictive factors of postpartum fatigue [1] and the effects of exercise on pregnancy and postpartum fatigue [14].
To the best of our knowledge, there is currently no in-depth systematic review and meta-analysis of nonpharmacological interventions speci c for postpartum fatigue. Therefore, the aim of this study was to identify existing nonpharmacological interventions offered to postnatal women and to examine their effectiveness for relieving postpartum fatigue.

Protocol and registration
The protocol has been registered in the International Prospective Register of Systematic Reviews (PROSPERO); registration number CRD42021234869.

Study design
This systematic review and meta-analysis has been reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement (PRISMA). The PRISMA checklist can be seen in Additional le 1.

Search strategy
The focus of the review was to examine nonpharmacological interventions for fatigue reduction in postpartum women. Seven electronic databases, including the Cochrane Library, PubMed, Embase, Web of Science, PsycINFO, CINAHL and ProQuest, were searched for articles published from inception until February Emtree terms and free terms [e.g., (postnatal OR postpartum OR delivery OR childbirth OR birth OR parturition OR labour OR pregnancy) AND (fatigue OR mental fatigue OR lassitude OR exhaust*) AND (randomized controlled trial OR controlled clinical trial OR cohort OR clinical trial) was used. The nal search strategies applied are shown in Additional le 2. Moreover, a manual search of reference lists was performed to thoroughly identify relevant studies that were missed. Two authors (XXX and XXX) performed the search process independently.

Eligibility/exclusion criteria for selecting studies
The inclusion criteria of this review were as follows: (1) Study design: Clinical trials adopting randomized controlled trials (RCTs), quasi-experimental, beforeand-after or prospective cohort study designs; (2) Participants: women aged 18 years or over who had a healthy pregnancy; and (3) Intervention: nonpharmacological interventions conducted during the women's postpartum period with the primary or secondary aim of decreasing fatigue symptoms. The intervention setting, frequency, timing and duration were not limited; (4) Comparison: usual care, placebo, waitlist or no interventions; and (5) Outcomes: the primary e cacy outcome was postpartum fatigue estimated as the rate or mean severity of fatigue. The second e cacy outcome was psychological variables, such as depression, anxiety or stress. The exclusion criteria were as follows: (1) duplicated publications (only the one with the most participants was included); (2) analyses of interventions based on postpartum fatigue in some special conditions, such as postpartum haemorrhage; and (3) studies without su cient data to be extracted.
After removing duplicates, two authors (XXX and XXX) independently screened the studies according to the inclusion criteria in 2 steps: 1) title and abstract screening and 2) full-text screening. A third author (XX) was consulted to reach a consensus when there was any uncertainty about the inclusion of an article.

Data extraction
A standardized data extraction sheet was used to extract important information from the included studies. The extracted data included rst author, publication year, country, study design, population, sample size (trial/control), intervention details (e.g., type, frequency and duration), control, evaluation time points, assessment tools and outcomes. Two authors (XXX and XXX) independently extracted the data, and any inconsistencies were resolved by a third author (XX).

Risk of bias summary
For RCTs, the Cochrane risk-of-bias tool was used for the quality assessment [15]. Studies were assessed based on seven criteria (random sequence generation, allocation concealment, blinding of participants and researchers, blinding of outcome assessor, incomplete outcomes data, selective reporting and other bias). Bias was evaluated as a judgement (high or low or unclear), and then each included study was rated as having a high, moderate or low risk of bias. The Risk of Bias in Nonrandomized Studies of Interventions was used to assess the risk of bias of non-RCTs [16]. Seven domains are evaluated in this tool (confounding, selection of participants into the study, classi cation of intervention, deviation from the intended interventions, missing data, measurements of outcomes and selection of the reported results). Two authors (XXX and XXX) assessed the risk of bias and evidence quality separately.
Disagreements were discussed with a third researcher (XX) to reach a consistent conclusion.

Data analysis
We performed a meta-analysis utilizing Review Manager 5.3. For continuous outcomes, we calculated mean differences (MDs) and 95% con dence intervals (CIs) if the outcomes were measured using the same tool. We used standardized mean differences (SMDs) and 95% CIs to combine studies when the same outcome was measured by adopting different tools [17]. For the SMD, ≤ 0.20, = 0.50, and ≥ 0.80 are designated as small, moderate and large effect sizes, respectively [18]. The heterogeneity among the analysed trials was examined by standard chi-square and I-square statistics. If the P value was > 0.1 or I 2 < 50%, it indicated that there was no observed heterogeneity, and the researchers employed a xed-effects model to combine the study results. If not, a randomeffects model analysis was used [19].

Results
The identi ed citations were imported into EndNote software and screened for duplicates. The initial search of 7 databases revealed 2955 references. A search of reference lists and OpenGrey revealed 3 other relevant studies. After removing 879 duplicates, the titles and abstracts of the remaining 2079 articles were screened, which excluded 2042 articles and left 37 full-text articles that were reviewed for eligibility. Twenty studies were excluded for being abstracts and protocols (n = 2), interventions were not conducted in the postpartum period (n = 6), could not nd the full text (n = 1), studies published in another language (n = 2), studies without fatigue outcomes (n = 8) and studies not involving clinical interventions (n = 1). Ultimately, 17 studies were included in this systematic review, and 13 studies met the criteria for meta-analysis. A PRISMA ow diagram illustrating the detailed study selection process is shown in Fig. 1.

Study characteristics
The study characteristics are summarized in Table 1. Studies were published between 2003 ~ 2020. The 17 included articles were conducted in different countries: China (n = 5), Iran (n = 4), the USA (n = 2), Canada (n = 2), Turkey (n = 2), Australia (n = 1) and the UK (n = 1). A total of 2142 participants were included in this systematic review. The sample size ranged from 27 to 356 participants in each trial. Eleven of the 17 included studies employed a randomized controlled trial design.
Four types of interventions were undertaken: exercise [12,[20][21][22][23](n = 5), psychoeducational intervention [13,[24][25][26][27][28][29] (n = 7), physical therapy [10,11,30] (n = 3) and drinking tea [31,32](n = 2). The intervention duration ranged from 1 day to 3 months. All included studies described the baseline assessments, with the scores for the intervention and control groups comparable at baseline. Additionally, the studies reported assessment scores immediately after the intervention and follow-up assessment scores at 1 month postintervention [31,32], 6 weeks [24,25,28] and 9 weeks postintervention [24], 2 months postintervention [20] Risk of bias of the evidence The quality of the study designs was low to moderate overall. Several methodological limitations were observed in the critical appraisal. Quality assessments of the 11 included studies using an RCT design, with a risk of bias graph and risk of bias summary, are described in Fig. 2 and Fig. 3. All of the studies reported using randomization; however, two articles did not provide detailed information about the randomization method. Six studies reported su cient details about allocation concealment. Blinding of the participants and researchers who delivered the interventions was not feasible because the interventions were easy to identify. Therefore, all of the studies are at a high risk of performance bias. Regarding detection bias, only four studies provided su cient explanations. Except for one study, all RCT studies gave clear information about the incomplete outcome data. No reporting bias was found in the included RCTs.
The results of the quality appraisal of the six nonrandomized studies are displayed in Table 2. Bias due to confounding factors, selection of participants into the study and classi cation of interventions were low for all included nonrandomized studies. Three articles were at moderate risk of bias due to deviations from the intended intervention. All of the studies were reasonably reported and addressed missing data. In regard to bias in the measurement of outcomes, considering that the interventions were not blinded to the participants, all studies were judged as at moderate risk of bias. Bias in selection of the reported results was not observed.

Meta-analysis results
For the purposes of meta-analysis, postpartum interventions were grouped into four broad categories: exercise, psychoeducational interventions, physical therapy and drinking tea. Only one trial [27] reported the postpartum fatigue rate. Three trials [21,23,24] without su cient original data for meta-analysis were thus not included. Ultimately, thirteen studies that reported the mean fatigue scores and standard deviations were included in the meta-analysis. For the secondary outcomes, since more than two studies reported depression, a statistical combination was performed regarding this psychological outcome.
Effectiveness of exercise

Effectiveness of physical therapy
Three trials showed the effectiveness of physical therapy on posttreatment fatigue severity (Fig. 6). Signi cant improvements were observed in the participants who received physical therapy in comparison with the participants in the control groups. There was substantial evidence of high heterogeneity (I 2 = 74%, P = 0.02), so a random-effect model was applied. The pooled SMD was − 0.50 (95% CI=-0.96 to -0.03, Z = 2.09, P = 0.04).

Effectiveness of drinking tea
The effectiveness of drinking tea on fatigue and depression at postintervention and at the 2-week follow-up were presented in two trials (Fig. 7). At postintervention, signi cant differences were noted between the intervention and control groups in regard to fatigue and depression. No signi cant heterogeneity was found in terms of fatigue and depression (I 2 = 0%, P = 0.44; I 2 = 0%, P = 0.74). Therefore, a xed-effects model was used. The pooled MD was the overall health of postpartum women. A meta-analysis [35] indicated that postpartum exercise was bene cial for decreasing postpartum fatigue (SMD = 0.36). The bene ts of exercise on fatigue are worth a rming. However, postpartum women are still at high risk for physical inactivity and rarely understand how to engage in postpartum exercise [33]. The American College of Obstetricians and Gynaecologists (ACOG) suggested that physical activity, including performing muscle-toning exercises, could be restarted 6 weeks after childbirth if the delivery was uncomplicated [36]. Daily 20 ~ 30 min of regular moderateto-intense exercise is recommended [37]. A previous study reported that supervised postpartum exercise lasting more than eight weeks is suggested for reducing postpartum fatigue [14]. Therefore, clinical staff should give su cient explanations and evidence-based instructions for postnatal exercises to help reduce women's postpartum fatigue and facilitate their postpartum rehabilitation.
This is inconsistent with the ndings of a previous meta-analysis [38], which reported that exercise reduced symptoms of depression (SMD=-0.81, 95% CI=-1.53 to -0.10) of mothers who had been diagnosed with depression. The insigni cant results may be explained by the fact that the two studies [12,22] in our review did not include participants with obvious depressed symptoms at baseline. Therefore, a signi cant reduction in depression was di cult to observe after the exercise intervention. It is worth noting that in Yang et al. [12]'s study, women reported feelings of mood relaxation and pressure relief after the intervention, which indicated that exercise may have potential e cacy for women's mental health. More research conducting exercise interventions among puerperae who have severe symptoms of psychological problems is needed to con rm the true effect of exercise on mothers' psychological well-being.
Five studies performing psychoeducational interventions showed no obvious differences in postpartum fatigue and depression between the two groups at either the postintervention or 8-week follow-up. Although psychoeducational interventions usually involve various aspects associated with postnatal health, including fatigue, sleep, infection, nutrition, breastfeeding and so on, this type of intervention was mostly delivered via home visits, lea et/booklets and home calls. It is di cult to guarantee the good compliance of participants due to a lack of su cient supervision and guidance. Therefore, it may be di cult to perform psychoeducational interventions effectively. With the development of rapid electronic technology, people's requests for health services have also facilitated instant communication and promoted e ciency in the transmission of information [39]. A previous study reported that web-based interventions had better effects on improving postnatal depression than home-based postnatal psychoeducational interventions [40] and suggested that web-based interventions should be introduced to mothers for better postnatal care. Hence, psychoeducational interventions could be combined with internet technology [41] or smartphones [42] in the future to improve the participation of women, observe the compliance of the participants and better manage the intervention implementation.
The ndings from our meta-analysis of three studies [10,11,30]  controllability. Warm showers, as a comfort measure, are closely associated with increased relaxation and tension reduction [43]. It is a safe and effective measure for healthy, labouring women who are experiencing physical and psychological issues [43]. The bene ts of lavender oil on postpartum fatigue were reported in another RCT conducted among pregnant women [44]. Participants in either the lavender and footbath or lavender alone group showed that fatigue was improved signi cantly at 6 weeks postpartum. Although the e cacy of mother-infant skin-to-skin on fatigue was not observed in Funda et al.'s study, a recently published meta-analysis demonstrated that mother-infant skin-to-skin was a cost-effective, simple and feasible approach for postpartum depression [45]. Considering that physical therapies are relatively safe and effective, physical therapies such as footbaths [44], re exology[46], warm showers [30] and lavender oil [11], which show effects on fatigue reduction and mental health improvement, could be used in combination to enhance the intervention e cacy. Among the three included studies, only Vaziri et al.'s study examined the e cacy of lavender oil aroma for psychological outcomes, including distress and mood, and positive effects were observed. More research is needed to explore its effectiveness for mental health.
In terms of drinking tea, the results showed that there were signi cant differences in postpartum fatigue between the two groups at postintervention (MD= -3.12, 95% CI=-5.44 to -0.80, Z = 2.64, P = 0.008), but no signi cant differences were found at the 2-week follow-up. The positive effects of drinking tea on relieving depression were obvious at the postintervention and 2-week follow-up. Postnatal women were required to smell (appreciate) the aroma before drinking the tea. Aromatherapy has been used for pain and anxiety relief, relaxation, and creating a pleasant feeling in mothers [47][48][49], which could help to relieve fatigue and depressive emotions. Women in the intervention group reported the bene ts of drinking chamomile tea to be facilitating emotional stability and relaxation and having an aromatic fragrance, which could calm restlessness, facilitate the postnatal paternity relationship, and alleviate postpartum fatigue [50]. However, the positive effects did not last long after the intervention. Thus, multiple daily consumption of tea may be recommended to assess its lasting effect in consideration of its convenience.

Strengths and limitations
To the best of our knowledge, this is the rst systematic review and meta-analysis on nonpharmacological interventions for reducing postpartum fatigue. This review was rigorous and based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statements as well as a prospective registered protocol. Another strength was that randomized controlled trials and controlled clinical trials were included in this review, which provides good standards for evidence-based research.
There were some limitations of this systematic review. First, a limitation of the review was that non-English electronic databases were not searched, which may cause language bias [51]. Second, the number of included studies for each type of intervention was small. The heterogeneity in the statistical combinations of exercise, psychoeducational intervention and physical therapy was signi cant. These factors may have an impact on the reliability of the pooled results. Third, a limitation lies in the risk of bias within the included studies. The potential biases may have in uenced the reported effect estimates; therefore, caution is required when interpreting the ndings of our study.
The results from this systematic review and meta-analysis provide evidence that nonpharmacological interventions, including exercise, physical therapy and drinking tea, are effective in reducing postpartum fatigue. Detailed and evidence-based instructions involving exercise frequency and duration should be offered to puerperae. Considering that physical therapies are relatively safe, they could be used in combination to enhance the intervention e cacy. Multiple daily cups of tea may be recommended to assess its lasting effect. The effects of psychoeducation were not noted, and future research could integrate psychoeducation with internet technology or smartphones to improve the compliance of the participants. The effectiveness of fatigue-related nonpharmacological interventions on psychological outcomes still needs to be further investigated due to the limited number of studies.      Forest plots for meta-analysis of physical therapy on postintervention fatigue scores.

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