Effects of antenatal hypnosis on maternal salivary cortisol during childbirth and six weeks postpartum-A randomized controlled trial.

BACKGROUND: Cortisol has been used to capture psychophysiological stress during childbirth and postpartum wellbeing. We explored the effect of a brief antenatal training course in self-hypnosis on salivary cortisol during childbirth and 6 weeks postpartum. METHODS: In a randomized, controlled trial conducted at Aarhus University Hospital Skejby Denmark during the period January 2010 until October 2010, a total of 349 healthy nulliparous women were included. They were randomly allocated to a hypnosis group (n = 136) receiving three one-hour lessons in self-hypnosis with additional audio-recordings, a relaxation group (n = 134) receiving three one-hour lessons in various relaxation methods with audio-recordings for additional training, and a usual care group (n = 79) receiving ordinary antenatal care only. Salivary cortisol samples were collected during childbirth (at the beginning of the pushing state, 30 minutes, and 2 hours after childbirth), and 6 weeks postpartum (at wake up, 30 minutes after wake up, and evening). Cortisol concentrations were compared using a linear mixed-effects model. Correlations between cortisol concentrations and length of birth, experienced pain and calmness during birth were examined by a Spearman rank correlation test. FINDINGS: During childbirth, week correlations were found between cortisol concentrations 30 minutes after childbirth and length of birth. In the beginning of the pushing state and 2 hours after childbirth, we found a tendency towards higher cortisol concentrations in the hypnosis group compared to the other two groups (hypnosis versus relaxation p = 0.02 and 0.03, hypnosis versus usual care p = 0.08 and 0.05). No differences were observed in cortisol concentrations between the groups 30 minutes after childbirth (hypnosis versus relaxation p = 0.08, hypnosis versus usual care 0.10) or 6 weeks postpartum (hypnosis versus relaxation: p = 0.85, 0.51, and 0.68, hypnosis versus usual care: p = 0.85, 0.93, and 0.96). CONCLUSION: Antenatal hypnosis training may increase the release of cortisol during childbirth with no long-term consequences. Further research is needed to help interpret these findings.

Comfort in Labor: "Like Being Able to Exhale".

Comfort is a fundamental human need to seek relief, ease, and transcendence. Comfort is relevant to women in labor who experience intense pain and mixed emotions. The subjective meaning of comfort in labor for women is not fully understood. This work was part of a phenomenological study of the experience of childbirth, in which the dynamic of keeping-it-together-falling-apart was identified as an essential quality of women's perceptions of childbirth. Comfort was a salient element of keeping-it-together-falling-apart. In this report, the concept of comfort is explored in greater depth, using qualitative descriptive analysis. Eight participants, aged 23 to 38 years, with spontaneous vaginal births, were each interviewed twice about the childbirth experience. Comfort was a holistic experience of relaxation and relief, where the needs of the body and the person were being met. Comfort and pain coexisted with each other, and relief of pain did not always provide comfort. Women had an innate knowledge of comfort, but their capacity for choice was at times restricted by caregivers in the hospital. There are aspects of labor care that do not support comfort, particularly as it relates to mobility and choice. Prioritizing comfort as well as pain relief may contribute to a more holistic, satisfying birth experience for women.

Labor pain control and associated factors among women who gave birth at Leku primary hospital, southern Ethiopia.

OBJECTIVE: To assess labor pain control and associated factors among women who give birth at Leku primary hospital, southern Ethiopia, 2018/19. A systematic random sampling technique was used to select 404 mothers who gave birth at Leku hospital during the data collection period. Data were collected by two first degree midwives immediately after delivery using Labor Agentry Scale (LAS). RESULTS: In this study, 404 mothers were participated making the response rate of 100%. Among the participants, 104 (25.7%) of mothers reported Mild control of labor pain. Maternal age of 19 to 24 year AOR = 5.85 (95% CI 2.14, 15.98), being farmer AOR = 2.5 (1.14, 5.57), primi-para AOR = 0.13 (0.06, 0.3), good family support AOR = 2.8 (1.49, 5.3), short duration of labor (< 12 h) AOR = 3.2 (1.65, 6.23) and history of pregnancy loss AOR = 0.06 (0.03, 0.14) were significantly associated with greater control of labor pain. In general, compared to other studies, the level of labor pain control is good in this study area. Enhancing factors of labor pain control have to be strengthened to increase greater control of labor pain. Qualitative research is highly recommended to identify cultural factors related to labor pain control and management.

Evaluation of different doses of transcutaneous nerve stimulation for pain relief during labour: a randomized controlled trial.

BACKGROUND: Pain during labour is one of the most intense pain that women may experience in their lifetime. There are several non-pharmacological analgesic methods to relieve pain during labour, among them transcutaneous electrical nerve stimulation (TENS). TENS is a low-frequency electrotherapy technique, analgesic type, generally used in musculoskeletal pathology, but it has also come to be used as an alternative treatment during labour. The purpose of this study is to investigate the pain-relieving effect of a TENS application during labour and to find out the most effective dose. METHODS: This study is a randomized, double-blind, placebo-controlled trial. TENS therapy was initiated at the beginning of the active phase of labour. Participants were randomly assigned to three groups (21 per group: two active TENS and one placebo). Active TENS 1 intervention consisted in a constant frequency of 100-Hz, 100-µs, active TENS 2 intervention consisted in a varying high-frequency (80-100 Hz), 350 µs, and in a placebo group, participants were connected to the TENS unit without electrical stimulation. TENS was applied with two self-adhesive electrodes placed parallel to the spinal cord (T10-L1 and S2-S4 levels). The primary outcome was pain intensity (0-10 cm) measured on a visual analogue scale (VAS) at several stages (at baseline and at 10 and 30 min later). Secondary outcomes included women's satisfaction (via the Care in Obstetrics: Measure for Testing Satisfaction scale). RESULTS: Sixty-three women participated. Regarding baseline characteristics, no differences were found among the three groups. The active TENS 2 group obtained an improvement with clinically significant VAS results (- 2.9, 95% confidence interval - 4.1 to - 1.6, p <  0.001). Regarding satisfaction, the results also revealed better results in the active TENS than in the placebo group. CONCLUSIONS: TENS with high frequencies modified in time as well as high pulse width are effective for relieving labour pain, and they are well considered by pregnant participants. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03137251 . Registered on 2 May 2017.

No. 355-Physiologic Basis of Pain in Labour and Delivery: An Evidence-Based Approach to its Management.

OBJECTIVE: To review the evidence relating to nonpharmacological approaches in the management of pain during labour and delivery. To formulate recommendations for the usage of nonpharmacological approaches to pain management. OPTIONS: Nonpharmacological methods available for pain management during labour and delivery exist. These should be included in the counselling and care of women. EVIDENCE: PubMed and Medline were searched for articles in French and English on subjects related to "breastfeeding," "pain," "epidural," "anaesthesia," "analgesia," "labour," "labor," and combined with "gate control theory," "alternative therapies," "massage," "position," "mobility," "TENS," "bathing," "DNIC," "acupuncture," "acupressure," "sterile water injection," "higher center," "control mind," "cognitive structuring," "holistic health," "complementary therapy(ies)," "breathing," "relaxation," "mental imagery," "visualization," "mind focusing," "hypnosis," "auto-hypnosis," "sophrology," "mind and body interventions," "music," "odors," "biofeedback," "Lamaze," "Bonapace," "prenatal training," "gymnastic," "chanting," "haptonomy," "environment," "transcutaneous electrical stimulus-stimulation," "antenatal education," "support," "continuous support," "psychosocial support," "psychosomatic medicine," "supportive care," "companion," "intrapartum care," "nurse," "midwife(ves)," "father," "doula," "caregiver," " hormones," "oxytocin," "endorphin," "prolactin," "catecholamine," "adrenaline," and "noradrenaline" from 1990 to December 2015. Additional studies were identified by screening reference lists from selected studies and from expert suggestions. No language restrictions were applied. VALIDATION METHODS: The quality of the evidence is rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. Recommendations for practice are ranked according to the method described in this report. BENEFITS, RISKS, AND COST: The nonpharmacological method encourages an incremental approach to pain management that contributes to reduced interventions through optimal use of the woman's neurophysiologic and endocrine resources and a better understanding of the physiology of stress and pain during labour. GUIDELINE UPDATE: The guideline will be reviewed 5 years after publication to decide whether all of part of the guideline should be updated. However, if important new evidence is published prior to the 5-year cycles, the review process may be accelerated for a more rapid update of some recommendations. SPONSORS: This guideline was developed with resources funded by The Society of Obstetricians and Gynaecologists of Canada. SUMMARY STATEMENTS: RECOMMENDATIONS.

The best encouraging persons in labor: A content analysis of Iranian mothers' experiences of labor support.

BACKGROUND AND AIMS: The process of giving birth is very stressing for the mother. Meanwhile, maternity ward staff's lack of awareness of mothers' fears make mothers feel lonely and helpless. This study aimed to explore women's perceptions of labor support during vaginal delivery. MATERIALS AND METHODS: This exploratory qualitative study used qualitative content analysis to explore Iranian mothers' experiences of labor support. Data were collected using observations and semi-structured interviews with 25 individuals. The participants were recruited through a purposive sampling method. RESULTS: Three categories, including "involvement of the spouse in the labor process", "asking for a companion during labor", and "mother's self-care to cope with labor pain", emerged during data analysis. These categories were merged to form the main theme of "trying to comply with the labor process". CONCLUSION: Women believed that the presence of a companion, e.g. their husband, a family member, or a doula, during labor helped them better deal with the labor process, particularly when they felt lonely. Health care providers are expected to consider the needs of mothers and try to provide holistic support for mothers during labor pain. IMPLICATIONS FOR PRACTICE: It seems that some mothers adopted particular coping strategies without receiving any relevant training. It is noteworthy that although mothers may make every effort to minimize their pain, health professionals should also practice medical approaches to help them through the process of labor.

Systematic Review of Hydrotherapy Research: Does a Warm Bath in Labor Promote Normal Physiologic Childbirth?

Health sciences research was systematically reviewed to assess randomized controlled trials of standard care versus immersion hydrotherapy in labor before conventional childbirth. Seven studies of 2615 women were included. Six trials examined hydrotherapy in midwifery care and found an effect of pain relief; of these, 2 examined analgesia and found reduced use among women who bathed in labor. One study each found that hydrotherapy reduced maternal anxiety and fetal malpresentation, increased maternal satisfaction with movement and privacy, and resulted in cervical dilation progress equivalent to standard labor augmentation practices. Studies examined more than 30 fetal and neonatal outcomes, and no benefit or harm of hydrotherapy was identified. Two trials had anomalous findings of increased newborn resuscitation or nursery admission after hydrotherapy, which were not supported by additional results in the same or other studies. Review findings demonstrate that intrapartum immersion hydrotherapy is a helpful and benign practice. Hydrotherapy facilitates physiologic childbirth and may increase satisfaction with care. Maternity care providers are recommended to include hydrotherapy among routine labor pain management options and consider immersion to promote progress of normal or protracted labor, particularly among women with preferences to avoid obstetric medications and procedures.

No Pain Labor & Delivery: A Global Health Initiative's Impact on Clinical Outcomes in China.

The availability of labor analgesia is highly variable in the People's Republic of China. There are widespread misconceptions, by both parturients and health care providers, that labor epidural analgesia is harmful to mother and baby. Meanwhile, China has one of the highest cesarean delivery rates in the world, exceeding 50%. The goal of the nongovernmental No Pain Labor & Delivery (NPLD) is to facilitate sustainable increases in vaginal delivery rates by increasing access to safe neuraxial labor analgesia, thereby decreasing the cesarean delivery rate. NPLD was launched in 2008 with the stated goal of improving labor outcome in China by increasing the absolute labor epidural analgesia rate by 10%. NPLD established 10 training centers over a 10-year period. We hypothesized that increased availability of labor analgesia would result in reduced requests for cesarean delivery and better labor outcomes for mother and baby. Multidisciplinary teams of Western clinicians and support staff traveled to China for 8 to 10 days once a year. The approach involved establishing 24/7 obstetric anesthesia coverage in Chinese hospitals through education and modeling multidisciplinary approaches, including problem-based learning discussions, bedside teaching, daily debriefings, simulation training drills, and weekend conferences. As of November 2015, NPLD has engaged with 31 hospitals. At 24 of these sites, 24/7 obstetric anesthesia coverage has been established and labor epidural analgesia rates have exceeded 50%. Lower rates of cesarean delivery, episiotomy, postpartum blood transfusion, and better neonatal outcomes were documented in 3 impact studies comprising approximately 55,000 deliveries. Changes in practice guidelines, medical policy, and billing codes have been implemented in conjunction with the modernization of perinatal practice that has occurred concurrently in China since the first NPLD trip in 2008.

Alternativas analgésicas al dolor de parto / Analgesic alternatives for labour pain

Introducción: Actualmente se ha observado un mayor interés por parte de las madres y su entorno, por la aplicación de otros métodos analgésicos no invasivos. Por lo tanto, es un tema de gran importancia para los profesionales de la salud relacionados con la atención al parto, los cuales deben desarrollar las habilidades necesarias para ayudar a aquellas mujeres que optan por un parto promovido por la aplicación alternativa de medidas analgésicas. Objetivos: Se pretende evaluar la efectividad y eficacia de las principales alternativas analgésicas al parto que la literatura científica nos ofrece. Metodología: Se ha realizado una búsqueda bibliográfica en las siguientes bases de datos: Medline, Pubmed, The Cochrane Database of Systematic Reviews y Ebsco. Resultados: Los estudios consultados reflejan que las diferentes alternativas analgésicas como la aplicación de electroterapia, acupuntura, masoterapia o termoterapia en el parto son efectivas en grado moderado en la reducción del dolor. Conclusiones: La aplicación de medidas analgésicas alternativas resulta de efectividad comprobada, no obstante, es necesaria la elaboración de mayores estudios clínicos con una metodología consensuada que avale la efectividad de dichas intervenciones (AU)

Introduction: Currently there has been an increased interest from mothers and their environment, by the application of other non-invasive analgesic methods. Therefore, it is a major issue for health professionals related to delivery care, which should develop the skills necessary to help those women who choose childbirth alternative promoted by the application of analgesic action. Objectives: We sought to evaluate the effectiveness and efficiency of the main alternatives analgesic delivery that literature offers us. Methods: We performed a literature search in the following databases: Medline, Pubmed, The Cochrane Database of Systematic Reviews and Ebsco. Results: The studies surveyed reflect that different alternatives as applying analgesic electrotherapy, acupuncture, massage therapy or thermotherapy in childbirth are moderate effective in reducing pain. Conclusions: The application of alternative analgesic action is proven effective, however, it is necessary the development of larger clinical studies with a methodology agreed to endorse the effectiveness of such interventions (AU)

[Clinical observation of the impacts and safety of electroacupuncture at Sanyinjiao (SP 6) on labor].

OBJECTIVE: To observe the impacts of electroacupuncture (EA) at Sanyinjiao (SP 6) on labor and assess its safety. METHODS: The random and single-blind method was adopted to divide 111 cases of the puerperas of natural delivery into an EA group (38 cases), a sham-acupuncture group (37 cases) and a blank control group (36 cases). In EA group, Sanyinjiao (SP 6) was selected and stimulated with Han's acupoint nerve stimulator (HANS). In the sham-acupuncture group, the puerperas were stimulated only with the needle tube, needle removed in advance and they felt subjectively to be needled. Afterward, the filiform needle was attached to Sanyinjiao (SP 6) with the needle tip wrapped with the adhesive plaster in advance, then HANS which one conducting wire was cut off in was connected. In the blank control group, no any treatment was applied, but the same indices were recorded at corresponding time points. The blood pressure and the heart rate of the puerperas as well as the heart rate of fetus were measured in 20 min of EA and 30 min after needle removal in three groups separately. The bleeding 24 h after labor and 1 min Apger score of the newborns were observed. RESULTS: In EA group, the active phase of the 1st labor stage ((4.38 +/- 1.76)h) was shorter than that ((5.28 +/- 2.41)h) in the blank control group and that ((5.38 +/- 2.36)h) in the sham-acupuncture group, presenting statistically significant differences (all P < 0.05). In the latent phase of the 1st labor stage and the 2nd and 3rd stages, in the comparison of the blood pressure and the heart rate of the puerperas as well as the heart rate of fetus after EA, the bleeding 24 h after labor and 1 min Apger score of the newborns among three groups, there were no statistically significant differences (all P > 0.05). CONCLUSION: EA at Sanyinjiao (SP 6) can shorten the duration of the active phase of the 1st labor stage. It is safe for either the puerpera or the fetus and can assist the parturition quality in clinic.

Effect of acupoint Sanyinjiao (SP6) moxibustion on the first stage of labor and uterine contractive pain in primiparae.

OBJECTIVE: To observe the effect of acupoint Sanyinjiao (SP6) moxibustion (S-Mox) on the duration of the first labor stage and uterine contractive pain in primiparae. METHODS: Sixty primipara women in labor were equally assigned according to their choice to three groups: women in the S-Mox group received bilateral S-Mox for 30 min, women in the non-acupoint group received moxibustion (Mox) applied on non-acupoints for 30 min, and those in the control group did not receive Mox intervention. The duration of the first labor stage was recorded and the degree of labor pain was estimated by a visual analogue scale (VAS) before and after Mox. RESULTS: The duration of the first stage active phase in the S-Mox group was significantly shorter than that in the other two groups (P<0.05, P<0.01); the VAS score after Mox was lower in the S-Mox group, showing a statistical difference in comparison with the control group (P<0.05). CONCLUSIONS: Applying S-Mox could markedly shorten the active phase of the first stage of labor and lower the VAS score of uterine contractive pain, which means alleviating the pain caused by vaginal delivery. Its mechanism is worthy of further study.

Biofeedback for pain management during labour.

BACKGROUND: Labour is often associated with pain and discomfort caused by a complex and subjective interaction of multiple factors, and should be understood within a multi-dimensional and multi-disciplinary framework. Within the non-pharmacological approach, biofeedback has focused on the acquisition of control over some physiological responses with the aid of electronic devices, allowing individuals to regulate some physical processes (such as pain) which are not usually under conscious control. The role of this behavioural approach for the management of pain during labour, as an addition to the standard prenatal care, has been never assessed systematically. This review is one in a series of Cochrane reviews examining pain relief in labour, which will contribute to an overview of systematic reviews of pain relief for women in labour (in preparation). OBJECTIVES: To examine the effectiveness of the use of biofeedback in prenatal lessons for managing pain during labour. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 March 2011), CENTRAL (The Cochrane Library 2011, Issue 1), PubMed (1950 to 20 March 2011), EMBASE (via OVID) (1980 to 24 March 2011), CINAHL (EBSCOhost) (1982 to 24 March 2011), and PsycINFO (via Ovid) (1806 to 24 March 2011). We searched for further studies in the reference lists of identified articles. SELECTION CRITERIA: Randomised controlled trials of any form of prenatal classes which included biofeedback, in any modality, in women with low-risk pregnancies. DATA COLLECTION AND ANALYSIS: Two authors independently assessed trial quality and extracted data. MAIN RESULTS: The review included four trials (186 women) that hugely differed in terms of the diversity of the intervention modalities and outcomes measured. Most trials assessed the effects of electromyographic biofeedback in women who were pregnant for the first time. The trials were judged to be at a high risk of bias due to the lack of data describing the sources of bias assessed. There was no significant evidence of a difference between biofeedback and control groups in terms of assisted vaginal birth, caesarean section, augmentation of labour and the use of pharmacological pain relief. The results of the included trials showed that the use of biofeedback to reduce the pain in women during labour is unproven. Electromyographic biofeedback may have some positive effects early in labour, but as labour progresses there is a need for additional pharmacological analgesia. AUTHORS' CONCLUSIONS: Despite some positive results shown in the included trials, there is insufficient evidence that biofeedback is effective for the management of pain during labour.

[Effect on moxibustion at Sanyinjiao (SP 6) for uterine contraction pain in labor: a randomized controlled trial].

OBJECTIVE: To investigate the effect of moxibustion at Sanyinjiao (SP 6) for uterine contraction pain in labor, and evaluate the safety of the parturient and newborn. METHODS: One hundred and seventy-four cases of singleton pregnancy and cephalic presentation primipara were single blinded and randomly divided into three groups: observation group (59 cases), placebo treated group (57 cases) and blank group (58 cases). The observation group was treated with moxibustion at Sanyinjiao (SP 6) for 30 min when the uterus cervix openning at 3 cm, the placebo treated group was treated with moxibustion at no acupoint for 30 min and the blank group was treated with routine labor nursing, the uterine contraction pain and the safety of the mother and infant were compared among three groups. RESULTS: 1) The uterine contraction pain was tested by Visual Analogue Scale (VAS): the scores of VAS in the observation group were obviously decreased after 15 min and 30 min of moxibustion (both P<0.05), there were no obvious changes of the VAS scores in placebo treated group and the blank group, the scores of VAS in observation group decreased much more obviously than those in the other two groups (all P<0.05); 2) Midwife rating of the uterine contraction pain: after 30 min of moxibustion, the effective rate of labor analgesia was 69.5% (41/59) in observation group, which was higher than that of 45.6% (26/57) in placebo treated group and 43.1% (25/58) in blank group, with significant differences between them (both P<0.05); 3) The postpartum hemorrhage amount of the observation group was obviously lower than those of placebo treated group and blank group (both P<0.05); 4) The Apgar score of newborn was higher in observation group and placebo treated group than that of blank group (both P<0.05). CONCLUSION: Moxibustion at Sanyinjiao (SP 6) can relieve the uterine contraction pain, and has no side effect to mother and infant, it is one of the safe, effective and simple non-drug analgesia methods.

Evaluation of pregabalin as an adjuvant to patient-controlled epidural analgesia during late termination of pregnancy.

INTRODUCTION: Late termination of pregnancy combines psychological distress with severe physical pain. The present study evaluated the benefit of adding oral pregabalin to epidural analgesia during this procedure. METHODS: Healthy women were randomly allocated to receive either oral pregabalin 150 mg/12 h or prazepam 10 mg/12 h at the induction of the late termination of pregnancy procedure. When they felt abdominal pain (numerical rating scale ranging from 0 [no pain] to 100 [worst pain possible]), patient-controlled epidural analgesia was activated and set to deliver ropivacaine 0.1% with sufentanil 0.25 µg/ml, 5 ml/h with a bolus dose of 5 ml/30 min. Rescue analgesia was available as needed by administration of 10 ml ropivacaine 0.1% (pain score less than 60/100) or 0.2% (at least 60/100). The primary outcome was the consumption of epidural analgesics. RESULTS: Forty-eight patients participated in the study. Demographic and obstetric data were similar. Pregabalin reduced total ropivacaine consumption 11.3 ± 3.2 mg/h (mean ± SD) versus 15.1 ± 4.9 mg/h in the prazepam group (P = 0.005), an effect related to a decrease in the need for rescue analgesia. In the pregabalin group, fewer women asked for rescue dose (75 vs. 96%; P = 0.048), and the number of rescue doses per patient was reduced (1 [0-2] vs. 2 [1-3]); median [interquartile range], P = 0.005), particularly the need for ropivacaine 0.2%. DISCUSSION: This is the first study considering the use of pregabalin for labor pain associated with late termination of pregnancy, showing that pregabalin 150 mg/12 h is a helpful adjuvant to epidural analgesia. Modulation of both visceral sensitization and affective component of pain may contribute to the benefits observed.

Pain acceptance and personal control in pain relief in two maternity care models: a cross-national comparison of Belgium and the Netherlands.

BACKGROUND: A cross-national comparison of Belgian and Dutch childbearing women allows us to gain insight into the relative importance of pain acceptance and personal control in pain relief in 2 maternity care models. Although Belgium and the Netherlands are neighbouring countries sharing the same language, political system and geography, they are characterised by a different organisation of health care, particularly in maternity care. In Belgium the medical risks of childbirth are emphasised but neutralised by a strong belief in the merits of the medical model. Labour pain is perceived as a needless inconvenience easily resolved by means of pain medication. In the Netherlands the midwifery model of care defines childbirth as a normal physiological process and family event. Labour pain is perceived as an ally in the birth process. METHODS: Women were invited to participate in the study by independent midwives and obstetricians during antenatal visits in 2004-2005. Two questionnaires were filled out by 611 women, one at 30 weeks of pregnancy and one within the first 2 weeks after childbirth either at home or in a hospital. However, only women having a hospital birth without obstetric intervention (N = 327) were included in this analysis. A logistic regression analysis has been performed. RESULTS: Labour pain acceptance and personal control in pain relief render pain medication use during labour less likely, especially if they occur together. Apart from this general result, we also find large country differences. Dutch women with a normal hospital birth are six times less likely to use pain medication during labour, compared to their Belgian counterparts. This country difference cannot be explained by labour pain acceptance, since - in contrast to our working hypothesis - Dutch and Belgian women giving birth in a hospital setting are characterised by a similar labour pain acceptance. Our findings suggest that personal control in pain relief can partially explain the country differences in coping with labour pain. For Dutch women we find that the use of pain medication is lowest if women experience control over the reception of pain medication and have a positive attitude towards labour pain. In Belgium however, not personal control over the use of pain relief predicts the use of pain medication, but negative attitudes towards labour. CONCLUSIONS: Apart from individual level determinants, such as length of labour or pain acceptance, our findings suggest that the maternity care context is of major importance in the study of the management of labour pain. The pain medication use in Belgian hospital maternity care is high and is very sensitive to negative attitudes towards labour pain. In the Netherlands, on the contrary, pain medication use is already low. This can partially be explained by a low degree of personal control in pain relief, especially when co-occurring with positive pain attitudes.

Pitfalls in chronobiology: a suggested analysis using intrathecal bupivacaine analgesia as an example.

BACKGROUND: The duration of analgesia from epidural administration of local anesthetics to parturients has been shown to follow a rhythmic pattern according to the time of drug administration. We studied whether there was a similar pattern after intrathecal administration of bupivacaine in parturients. In the course of the analysis, we came to believe that some data points coincident with provider shift changes were influenced by nonbiological, health care system factors, thus incorrectly suggesting a periodic signal in duration of labor analgesia. We developed graphical and analytical tools to help assess the influence of individual points on the chronobiological analysis. METHODS: Women with singleton term pregnancies in vertex presentation, cervical dilation 3 to 5 cm, pain score >50 mm (of 100 mm), and requesting labor analgesia were enrolled in this study. Patients received 2.5 mg of intrathecal bupivacaine in 2 mL using a combined spinal-epidural technique. Analgesia duration was the time from intrathecal injection until the first request for additional analgesia. The duration of analgesia was analyzed by visual inspection of the data, application of smoothing functions (Supersmoother; LOWESS and LOESS [locally weighted scatterplot smoothing functions]), analysis of variance, Cosinor (Chronos-Fit), Excel, and NONMEM (nonlinear mixed effect modeling). Confidence intervals (CIs) were determined by bootstrap analysis (1000 replications with replacement) using PLT Tools. RESULTS: Eighty-two women were included in the study. Examination of the raw data using 3 smoothing functions revealed a bimodal pattern, with a peak at approximately 0630 and a subsequent peak in the afternoon or evening, depending on the smoother. Analysis of variance did not identify any statistically significant difference between the duration of analgesia when intrathecal injection was given from midnight to 0600 compared with the duration of analgesia after intrathecal injection at other times. Chronos-Fit, Excel, and NONMEM produced identical results, with a mean duration of analgesia of 38.4 minutes (95% CI: 35.4-41.6 minutes), an 8-hour periodic waveform with an amplitude of 5.8 minutes (95% CI: 2.1-10.7 minutes), and a phase offset of 6.5 hours (95% CI: 5.4-8.0 hours) relative to midnight. The 8-hour periodic model did not reach statistical significance in 40% of bootstrap analyses, implying that statistical significance of the 8-hour periodic model was dependent on a subset of the data. Two data points before the change of shift at 0700 contributed most strongly to the statistical significance of the periodic waveform. Without these data points, there was no evidence of an 8-hour periodic waveform for intrathecal bupivacaine analgesia. CONCLUSION: Chronobiology includes the influence of external daily rhythms in the environment (e.g., nursing shifts) as well as human biological rhythms. We were able to distinguish the influence of an external rhythm by combining several novel analyses: (1) graphical presentation superimposing the raw data, external rhythms (e.g., nursing and anesthesia provider shifts), and smoothing functions; (2) graphical display of the contribution of each data point to the statistical significance; and (3) bootstrap analysis to identify whether the statistical significance was highly dependent on a data subset. These approaches suggested that 2 data points were likely artifacts of the change in nursing and anesthesia shifts. When these points were removed, there was no suggestion of biological rhythm in the duration of intrathecal bupivacaine analgesia.