Resting Heart Rate Variability and the Effects of Biofeedback Intervention in Women with Low-Risk Pregnancy and Prenatal Childbirth Fear

The effect of non-pharmacological prenatal interventions on fear of childbirth: an overview of systematic reviews and meta-analysis

BACKGROUND

During pregnancy and childbirth, alongside positive feelings, women undergo feelings such as fear of childbirth (FoC) and worry about its consequences, which could leave negative effects on the mother and her child during pregnancy, delivery, and postpartum. The study was carried out to determine the effectiveness of prenatal non-pharmacological interventions on reducing the FoC.

METHODS

The protocol of the study was registered in PROSPERO (ID: CRD42023468547). PubMed, Web of Science, Cochrane, Scopus, SID (Scientific Information Database) and Google Scholar search engine databases were systematically searched until July 27, 2023 with no limitation of time and limited to Persian and English studies in order to perform this overview. Certainty of evidence was assessed using GRADE, methodological quality using AMSTAR 2 and reporting quality using PRISMA score. Meta-analysis was performed on the data extracted from the original trials to evaluate the effect of different interventions on reducing the FoC. Sub-group analysis and meta-regression models were used to examine high heterogeneity, and sensitivity analysis was used to eliminate the effect of high risk of bias studies on the study findings.

RESULTS

Overall, 15 systematic reviews (SRs) were included in the overview, among which meta-analysis was performed in 9 studies. Considering methodological quality, these SRs were in low to critically low status and had relatively complete reports regarding reporting quality. Meta-analysis findings indicated that psychological interventions (SMD -2.02, 95% CI -2.69 to -1.36, 16 trials, 1057 participants, I2 = 95%) and prenatal educations (SMD -0.88, 95% CI -1.16 to -0.61, 4 trials, 432 participants, I2 = 72.8%) cause a significant reduction in FoC relative to prenatal usual cares with low certainty of evidence. Distraction techniques lead to a significant reduction in FoC relative to prenatal usual care with high certainty of evidence (SMD -0.75, 95% CI -1.18 to -0.33, 4 trials, 329 participants, I2 = 69%), but enhanced cares do not result in a significant decrease FoC relative to prenatal usual care with very low certainty of evidence (SMD -1.14, 95% CI -2.85 to 0.58, 3 trials, 232 participants, I2 = 97%).

CONCLUSIONS

Distraction techniques are effective in reducing FoC. Regarding the effect of psychological interventions and prenatal educations on the reduction of FoC, the findings indicated that the interventions may result in the reduction of FoC. Very uncertain evidence showed that enhanced cares are not effective in reducing the FoC.

Investigating heart rate variability measures during pregnancy as predictors of postpartum depression and anxiety: an exploratory study

Perinatal affective disorders are common, but standard screening measures reliant on subjective self-reports might not be sufficient to identify pregnant women at-risk for developing postpartum depression and anxiety. Lower heart rate variability (HRV) has been shown to be associated with affective disorders. The current exploratory study aimed to evaluate the predictive utility of late pregnancy HRV measurements of postpartum affective symptoms. A subset of participants from the BASIC study (Uppsala, Sweden) took part in a sub-study at pregnancy week 38 where HRV was measured before and after a mild stressor (n = 122). Outcome measures were 6-week postpartum depression and anxiety symptoms as quantified by the Edinburgh Postnatal Depression Scale (EPDS) and the Beck Anxiety Inventory (BAI). In total, 112 women were included in a depression outcome analysis and 106 women were included in an anxiety outcome analysis. Group comparisons indicated that lower pregnancy HRV was associated with depressive or anxious symptomatology at 6 weeks postpartum. Elastic net logistic regression analyses indicated that HRV indices alone were not predictive of postpartum depression or anxiety outcomes, but HRV indices were selected as predictors in a combined model with background and pregnancy variables. ROC curves for the combined models gave an area under the curve (AUC) of 0.93 for the depression outcome and an AUC of 0.83 for the anxiety outcome. HRV indices predictive of postpartum depression generally differed from those predictive of postpartum anxiety. HRV indices did not significantly improve prediction models comprised of psychological measures only in women with pregnancy depression or anxiety.

The effect of interventions in alleviating fear of childbirth in pregnant women: a systematic review

BACKGROUND

The Fear of Childbirth (FOC) is regarded as a general problem, which affects women's health and well-being, justifying demanding caesarean section. Several primary studies have been performed in relation to the interventions performed to reduce the fear of childbirth, which show contradictions between the results of these studies.

OBJECTIVE

This review aims to provide a comprehensive review of the different types of interventions used to reduce the fear of childbirth in pregnant mothers.

METHODS

In this study, systematic review of study information related to the effect of different therapies on reducing the fear of childbirth using subject-related keywords and validated with MeSH in SID, MagIran, IranMedex, IranDoc, Embase, ProQuest, Scopus, PubMed, Web of Science (ISI) databases and Google Scholar Search Engine were extracted without any time limit until February 2021.

RESULTS

After removing duplicates and irrelevant works from among the 5396 articles found, 63 articles remained in the study. The participants in these 63 articles were 5415 cases and 5770 controls. In addition, three studies were on epidural anesthesia, 33 on the effects of psychotherapy, 19 on the effects of education, and eight on the influence of other interventions on alleviating FOC. As shown by the results, psychotherapy intervention and education decreased FOC significantly.

CONCLUSION

According to the results of this study, to prevent the fear of childbirth, pregnancy training and prenatal preparation courses are recommended to empower pregnant women. It also seems beneficial to use psychotherapy approaches for women who are afraid of childbirth.

Methods for Heart Rate Variability Biofeedback (HRVB): A Systematic Review and Guidelines

Heart Rate Variability Biofeedback (HRVB) has been widely used to improve cardiovascular health and well-being. HRVB is based on breathing at an individual's resonance frequency, which stimulates respiratory sinus arrhythmia (RSA) and the baroreflex. There is, however, no methodological consensus on how to apply HRVB, while details about the protocol used are often not well reported. Thus, the objectives of this systematic review are to describe the different HRVB protocols and detect methodological concerns. PsycINFO, CINALH, Medline and Web of Science were searched between 2000 and April 2021. Data extraction and quality assessment were based on PRISMA guidelines. A total of 143 studies were finally included from any scientific field and any type of sample. Three protocols for HRVB were found: (i) "Optimal RF" (n = 37), each participant breathes at their previously detected RF; (ii) "Individual RF" (n = 48), each participant follows a biofeedback device that shows the optimal breathing rate based on cardiovascular data in real time, and (iii) "Preset-pace RF" (n = 51), all participants breathe at the same rate rate, usually 6 breaths/minute. In addition, we found several methodological differences for applying HRVB in terms of number of weeks, duration of breathing or combination of laboratory and home sessions. Remarkably, almost 2/3 of the studies did not report enough information to replicate the HRVB protocol in terms of breathing duration, inhalation/exhalation ratio, breathing control or body position. Methodological guidelines and a checklist are proposed to enhance the methodological quality of future HRVB studies and increase the information reported.

Comparing prenatal and postpartum stress among women with previous adverse pregnancy outcomes and normal obstetric histories: A longitudinal cohort study

OBJECTIVE

The aim of this study was to compare subjectively and objectively measured stress during pregnancy and the three months postpartum in women with previous adverse pregnancy outcomes and women with normal obstetric histories.

METHODS

We recruited two cohorts in southwestern Finland for this longitudinal study: (1) pregnant women (n = 32) with histories of preterm births or late miscarriages January-December 2019 and (2) pregnant women (n = 30) with histories of full-term births October 2019-March 2020. We continuously measured heart rate variability (HRV) using a smartwatch from 12 to 15 weeks of pregnancy until three months postpartum, and subjective stress was assessed with a smartphone application.

RESULTS

We recruited the women in both cohorts at a median of 14.2 weeks of pregnancy. The women with previous adverse pregnancy outcomes delivered earlier and more often through Caesarean section compared with the women with normal obstetric histories. We found differences in subjective stress between the cohorts in pregnancy weeks 29 and 34. The cohort of women with previous adverse pregnancy outcomes had a higher root mean square of successive differences between normal heartbeats (RMSSD), a well-known HRV parameter, compared with the other cohort in pregnancy weeks 26 (64.9 vs 55.0, p = 0.04) and 32 (63.0 vs 52.3, p = 0.04). Subjective stress did not correlate with HRV parameters.

CONCLUSIONS

Women with previous adverse pregnancy outcomes do not suffer from stress in subsequent pregnancies more than women with normal obstetric histories. Healthcare professionals need to be aware that interindividual variation in stress during pregnancy is considerable.

Quantitative cardiac autonomic outcomes of hydrotherapy in women during the first stage of labor

Introduction

Most hydrotherapy studies during childbirth report findings related to pain using a widespread set of subjective measures. In this study, ECG biomarkers as quantitative cardiac autonomic outcomes were used to assess the effects of warm shower hydrotherapy on laboring women during the first stage of labor.

Methods

This was a prospective single-blind cohort study on stage I delivering women. Their cardiac autonomic function was assessed using heart rate variability (HRV) measures during a deep breathing test using point-of-care testing comprised of an HRV scanner system with wireless ECG enabling real-time data analysis and visualization. Labor pain and anxiety were assessed using the Visual Analog Scale for Pain (VASP) and the Beck Anxiety Inventory (BAI). A total of 105 pregnant women in the first stage of labor who received warm shower hydrotherapy, intravenous analgesia (scopolamine + sodium dipyrone), or spinal anesthetic (bupivacaine + morphine) were enrolled.

Results

In women during the first stage of labor, parasympathetic modulation reflected through RMSSD (root mean square of successive RR interval differences) was significantly reduced by hydrotherapy and intravenous analgesia (before vs. after mean rank diff. 35.73 and 65.93, respectively, p < 0.05). Overall HRV (SDNN, standard deviation of RR intervals) was significantly decreased only by intravenous analgesia (before vs. after mean rank diff. 65.43, p < 0.001). Mean heart rate was significantly increased by intravenous analgesia, while spinal anesthesia reduced it, and hydrotherapy did not alter it (before vs. after mean rank diff. -49.35*, 70.38*, -24.20 ^NS , respectively, *p < 0.05, ^NS not significant).

Conclusion

This study demonstrates that warm shower therapy may impact the sympathovagal balance via parasympathetic withdrawal in women during the initial stage of labor. The findings of this study provide quantitative support for using warm shower hydrotherapy during labor via point-of-care testing. The dependability of hydrotherapy as a non-pharmacological treatment is linked to the completion of more clinical research demonstrating quantitative evidence via outcome biomarkers to support indications on stress and birth progress.

A longitudinal investigation of the influence of psychological factors on nausea and vomiting in early pregnancy

The purpose of this study was to elucidate psychological factors that may influence nausea and vomiting during pregnancy (NVP) progression in early pregnancy based on longitudinal observations. Fifty-nine pregnant women completed the Rhodes Index of Nausea, Vomiting, and Retching (RINVR) and General Health Questionnaire-28 (GHQ-28), and recorded their resting heart rate with photoplethysmography for 5 min to determine heart rate variability (HRV) indexes at 7-9 weeks and 11-13 weeks of gestation with a 4-week interval. GHQ-28 scores (total and subclasses) and HRV indexes at 7-9 weeks were compared among groups classified according to the presence of severe NVP (RINVR ≥ 9 points) at the two measurement points. Among women without severe NVP at 7-9 weeks, women who developed severe NVP at 11-13 weeks had significantly higher levels of anxiety/insomnia in the GHQ-28 subclasses (p = 0.018). The cross-lagged relationship from anxiety/insomnia at 7-9 weeks to RINVR at 11-13 weeks was significant (β = 0.367, p &lt; 0.001). Among women with severe NVP at 7-9 weeks, women whose severe symptoms subsided at 11-13 weeks had significantly higher high-frequency (HF) power (p = 0.010), and women with relatively higher HF power demonstrated a significant reduction in RINVR (interaction effect, p = 0.035). During early pregnancy, women with strong anxiety/insomnia symptoms tend to have NVP symptoms that become more severe as the pregnancy progresses. The higher HF power in women whose severe NVP subsided within 4 weeks suggests a contribution of emotion regulation to early amelioration of NVP.

The Effect of Holistic Birth Support Strategies on Coping With Labor Pain, Birth Satisfaction, and Fear of Childbirth: A Randomized, Triple-Blind, Controlled Trial

The current study was aimed to evaluate the effects of interventions conducted in line with the coping with labor pain algorithm (holistic birth support strategies) on women's coping with labor pain, birth satisfaction, and fear of childbirth. The study is a single-center, parallel-group randomized, three-blind, controlled trial. The study was completed with 33 women in the experimental group and 31 in the control group. The mean score of the women in the experimental group from the Birth Satisfaction Scale (128.57 ± 5.83) was statistically significantly higher than that of the women in the control group (81.80 ± 7.73). The mean score of the women in the experimental group (61.96 ± 9.78) from the Wijma Birth Expectation/Experience Scale, Version B scale was statistically significantly lower than that of the women in the control group (148.64 ± 14.62). It was found that the women in the experimental group were able to better cope with labor pain, had higher birth satisfaction, and had less fear of childbirth.

A Technology-Based Pregnancy Health and Wellness Intervention (Two Happy Hearts): Case Study

BACKGROUND

The physical and emotional well-being of women is critical for healthy pregnancy and birth outcomes. The Two Happy Hearts intervention is a personalized mind-body program coached by community health workers that includes monitoring and reflecting on personal health, as well as practicing stress management strategies such as mindful breathing and movement.

OBJECTIVE

The aims of this study are to (1) test the daily use of a wearable device to objectively measure physical and emotional well-being along with subjective assessments during pregnancy, and (2) explore the user's engagement with the Two Happy Hearts intervention prototype, as well as understand their experiences with various intervention components.

METHODS

A case study with a mixed design was used. We recruited a 29-year-old woman at 33 weeks of gestation with a singleton pregnancy. She had no medical complications or physical restrictions, and she was enrolled in the Medi-Cal public health insurance plan. The participant engaged in the Two Happy Hearts intervention prototype from her third trimester until delivery. The Oura smart ring was used to continuously monitor objective physical and emotional states, such as resting heart rate, resting heart rate variability, sleep, and physical activity. In addition, the participant self-reported her physical and emotional health using the Two Happy Hearts mobile app-based 24-hour recall surveys (sleep quality and level of physical activity) and ecological momentary assessment (positive and negative emotions), as well as the Perceived Stress Scale, Center for Epidemiologic Studies Depression Scale, and State-Trait Anxiety Inventory. Engagement with the Two Happy Hearts intervention was recorded via both the smart ring and phone app, and user experiences were collected via Research Electronic Data Capture satisfaction surveys. Objective data from the Oura ring and subjective data on physical and emotional health were described. Regression plots and Pearson correlations between the objective and subjective data were presented, and content analysis was performed for the qualitative data.

RESULTS

Decreased resting heart rate was significantly correlated with increased heart rate variability (r=-0.92, P<.001). We found significant associations between self-reported responses and Oura ring measures: (1) positive emotions and heart rate variability (r=0.54, P<.001), (2) sleep quality and sleep score (r=0.52, P<.001), and (3) physical activity and step count (r=0.77, P<.001). In addition, deep sleep appeared to increase as light and rapid eye movement sleep decreased. The psychological measures of stress, depression, and anxiety appeared to decrease from baseline to post intervention. Furthermore, the participant had a high completion rate of the components of the Two Happy Hearts intervention prototype and shared several positive experiences, such as an increased self-efficacy and a normal delivery.

CONCLUSIONS

The Two Happy Hearts intervention prototype shows promise for potential use by underserved pregnant women.

Interventions to treat fear of childbirth in pregnancy: a systematic review and meta-analysis

Background

Between 5% and 14% of women suffer from fear of childbirth (FOC) which is associated with difficulties during birth and in postnatal psychological adjustment. Therefore, effective interventions are needed to improve outcomes for women. A systematic review and meta-analysis was used to identify effective interventions for treating women with FOC.

Methods

Literature searches were undertaken on online databases. Hand searches of reference lists were also carried out. Studies were included in the review if they recruited women with FOC and aimed to reduce FOC and/or improve birth outcomes. Data were synthesised qualitatively and quantitatively using meta-analysis. The literature searches provided a total of 4474 citations.

Results

After removing duplicates and screening through abstracts, titles and full texts, 66 papers from 48 studies were identified for inclusion in the review. Methodological quality was mixed with 30 out of 48 studies having a medium risk of bias. Interventions were categorised into six broad groups: cognitive behavioural therapy, other talking therapies, antenatal education, enhanced midwifery care, alternative interventions and interventions during labour. Results from the meta-analysis showed that most interventions reduced FOC, regardless of the approach (mean effect size = −1.27; z = −4.53, p < 0.0001) and that other talking therapies may reduce caesarean section rates (OR 0.48, 95% CI 0.48–0.90).

Conclusions

Poor methodological quality of studies limits conclusions that can be drawn; however, evidence suggests that most interventions investigated reduce FOC. Future high-quality randomised controlled trials are needed so that clear conclusions can be made.

Mind-Body Techniques in Pregnancy and Postpartum

Maternal stress can perturb physiology and psychiatric health leading to adverse outcomes. This review investigates the effectiveness of several mind-body therapies-namely biofeedback, progressive muscle relaxation, guided imagery, tai chi, and yoga-as interventions in reducing maternal stress and other pregnancy-related conditions. Through randomized trials, these techniques have shown promising benefits for reducing pain, high blood pressure, stress, anxiety, depressive symptoms, labor pain and outcomes, and postpartum mood disturbances. As these interventions are easy to implement, low cost, and safe to perform in pregnancy, they should be considered as alternative, nonpharmaceutical interventions to use during pregnancy and postpartum care.

Biocueing and ambulatory biofeedback to enhance emotion regulation: A review of studies investigating non-psychiatric and psychiatric populations

Over the last years, biofeedback applications are increasingly used to enhance interoceptive awareness and self-regulation, in psychiatry and beyond. These applications are used to strengthen emotion regulation skills by home training (ambulatory biofeedback) and real-time support in everyday life stressful situations (biocueing). Unfortunately, knowledge about the feasibility and effectivity of these applications is still scarce. Therefore, a systematic literature search was performed. In total, 30 studies (4 biocueing, 26 ambulatory biofeedback) were reviewed; 21 of these studies were conducted in non-psychiatric samples and 9 studies in psychiatric samples. Study characteristics, biofeedback characteristics, effectivity and feasibility outcomes were extracted. Despite the rapid advances in wearable technology, only a few biocueing studies were found. In the majority of the studies significant positive effects were found on self-reported (stress-related) psychological measures. Significant improvements on physiological measures were also reported, though these measures were used less frequently. Feasibility of the applications was often reported as sufficient, though not adequately assessed in most studies. Taken into account the small sample sizes and the limited quality of the majority of the studies in this recently emerging field, biocueing and ambulatory biofeedback interventions showed promising results. Future research is expected to be focusing on biocueing as a just-in-time adaptive intervention. To establish this research field, closer cooperation between research groups, use of more rigorous as well as individually tailored research designs and more valid feasibility and effectivity assessment are recommended.

Determination of minimal recording period to assess resting heart rate variability during pregnancy

Traditionally, resting heart rate variability (rHRV) is measured for 10 min using the last 5 min for analyses (e.g., criterion period). It is unknown whether the measurement period can be shortened in pregnant women as there are currently no established standards. We aimed to compare shorter time segments (e.g., from the 1st to 10th minutes) of the parasympathetic index natural logarithm transformation of root mean square of successive R–R differences (Ln rMSSD) with the criterion period in pregnant and nonpregnant women. Twelve pregnant (age: 30.8 ± 3.4 years; gestational age: 20.1 ± 5.0 weeks) and 15 nonpregnant women (age: 29.8 ± 4.0 years) were included. rHRV was measured using a portable heart rate monitor for 10 min while sitting. Ln rMSSD difference/agreement between shorter time segments and criterion period was analyzed. The result observed between the 4th–5th minutes was the shortest time segment not different from/highly agreed with the criterion period in pregnant women (difference [95% confidence interval (CI)]: −0.10 [−0.22 to 0.02]/bias ± 1.96 × SD: −0.06 [−0.38 to 0.25]). In nonpregnant women, the 2nd–3rd-minute segment was the shortest with similar results (difference [95% CI]: −0.04 [−0.15 to 0.07]/bias ± 1.96 × SD: −0.03 [−0.39 to 0.32]). The Ln rMSSD was found to be stable from the 5th–10th minutes and the 3rd–10th minutes in pregnant and nonpregnant women, respectively. A shortened rHRV assessment can increase its applicability in clinical/exercise-training settings.

Novelty Ln rMSSD can be measured for 5 min in pregnant women, with the last 1-min segment analyzed. The last 1-min segment from 3 min can be used for rHRV measurement in nonpregnant women. The shortened rHRV assessment can facilitate its applicability in clinical/exercise-training settings.

Fear and Anxiety Disorders Related to Childbirth: Epidemiological and Therapeutic Issues

PURPOSE OF REVIEW

This paper seeks to identify the risk factors of fear of childbirth (FOC) and posttraumatic stress disorder (PTSD) related to birth and reviews the efficacy of their respective screening tools and therapeutic interventions.

RECENT FINDINGS

Biofeedback, hypnosis, internet-based cognitive behavioral therapy, and antenatal education are promising treatments for FOC. Training midwives to address traumatic birth experiences could help in preventing PTSD. A shorter more pragmatic screening tool for FOC than the Wijma Delivery Expectancy/Experience Questionnaire (WDEQ) is needed. Women with PTSD attributed a mismatch between the expected mode of delivery (MOD) and the actual MOD as the cause of their trauma. A history of mental health disorders, lack of social support, previous negative birth experiences, and MOD are correlated to FOC and postpartum PTSD. Psycho-education and CBT-based treatments have been found to reduce levels of FOC and PTSD.