acupressure to reduce labor pain

Acta Obstetricia et Gynecologica. 2010; 89: 1453–1459

MAIN RESEARCH ARTICLE

Acupressure to reduce labor pain: a randomized controlled trial

ANNA HJELMSTEDT1, SHEELA T. SHENOY2, ELISABETH STENER-VICTORIN3,MATS LEKANDER4, MAMTA BHAT2, LEENA BALAKUMARAN5 &ULLA WALDENSTRÖM1

1Department of Women’s and Children’s Health, Division of Reproductive and Perinatal Health, Karolinska Institutet,Stockholm, Sweden, 2Department of Obstetrics and Gynaecology, Medical College, Trivandrum, India, 3Institute ofNeuroscience and Physiology, Department of Physiology, Sahlgrenska Academy, University of Gothenburg, Sweden,4Department of Clinical Neuroscience, Section of Psychology and Osher Center for Integrative Medicine, KarolinskaInstitutet, Stockholm and Sweden Stress Research Institute, Stockholm University, Stockholm, Sweden, and 5PopulationHealth and Research Institute, Medical College, Trivandrum, India

AbstractObjective.To evaluate the effect of acupressure administered during the active phase of labor on nulliparous women’s ratings oflabor pain. Design. Randomized controlled trial. Setting. Public hospital in India. Sample. Seventy-one women randomized toreceive acupressure at acupuncture point spleen 6 (SP6) on both legs during contractions over a 30-minute period(acupressure group), 71 women to receive light touch at SP6 on both legs during the same period of time (touch group)and 70 women to receive standard care (standard care group). Methods. Experience of in-labor pain was assessed by visualanalog scale at baseline before treatment, immediately after treatment, and at 30, 60 and 120 minutes after treatment. Mainoutcome measure. Labor pain intensity at different time intervals after treatment compared with before treatment. Results. Areduction of in-labor pain was found in the acupressure group and was most noticeable immediately after treatment(acupressure group vs. standard care group p < 0.001; acupressure group vs. touch group p < 0.001). Conclusion. Acupressureseems to reduce pain during the active phase of labor in nulliparous women giving birth in a context in which social support andepidural analgesia are not available. However, the treatment effect is small which suggests that acupressure may be mosteffective during the initial phase of labor.

Key words: Acupressure, coping; labor, pain, randomized control trial

Introduction

Complementary and alternative methods to managelabor pain have become increasingly popular inhigh-income countries and they are often used as asupplement to rather than a replacement for pharma-cological methods such as epidural analgesia (1). Inlow-income countries where pharmacological painrelief may not be available, complementary methodsmay be the only option to decrease pain in labor.Complementary and alternative methods comprise awide range of heterogeneous and often sparsely eval-uated methods, one of which is acupressure. This

method is built on the same principles as acupunc-ture, but the needles are replaced by pressure, with theadvantage that no equipment is required and that theskin is not penetrated.To our knowledge only two studies have been

published evaluating the effect of acupressure duringlabor, one conducted in South Korea and one inTaiwan (2,3). In the Korean study, it was foundthat women who received acupressure at spleen6 (SP6) which is an acupuncture point located onthe lower leg, rated the labor pain as being less thanthe rating given by the women who only receivedtouch at the same point (2). The results of the

Correspondence: Anna Hjelmstedt, Division of Reproductive and Perinatal Health, Department of Women’s and Children’s Health, Retzius väg 13 A, KarolinskaInstitutet, 171 77 Stockholm, Sweden. E-mail: [email protected].

(Received 7 November 2009; accepted 8 July 2010)

ISSN 0001-6349 print/ISSN 1600-0412 online � 2010 Informa HealthcareDOI: 10.3109/00016349.2010.514323

Taiwanese study showed a greater reduction of painduring the active phase of the first stage of labor inwomen who received acupressure at the Large Intes-tinal 4 and Bladder 67 acupuncture points comparedwith a non-treated control group. The Large Intesti-nal 4 is located on the dorsum of the hand andBladder 67 on the lateral foot. No statistical differ-ences in pain assessments were found between theacupressure group and women who received effleu-rage (light skin stroking), or between the effleuragegroup and the control group (3). Differences betweenthe two studies regarding design and sample size makeit difficult to draw valid conclusions about the effect ofacupressure. Additional research has been requestedto elucidate the potential effects of acupressure onlabor pain (4).The aim of the present study was to evaluate

the effect of acupressure on acupoint SP6 as in theKorean study, and using a 3-arm design as in theTaiwanese study. Pressure on SP6 causes afferentactivity in the tibial nerve which enters the spinalcord at segmental level L4–S1, corresponding tothe innervation of the uterus and cervix (5). Theprimary outcome was the women’s assessment ofin-labor pain at different time intervals after treatmentcompared with before treatment. The secondary out-comes were retrospective ratings of labor pain, copingwith labor pain and experience of childbirth.The study was conducted in a large public hospital

in India where epidural analgesia is not an option innormal labor, and to which women cannot bring acompanion.

Material and methods

The recruitment of participants to the studytook place during the period September 1, 2007 toApril 31, 2008 at Sree Avittom Thirunal Hospital inTrivandrum, India. Sree Avittom Thirunal Hospitalis a public hospital with approximately 13,000 deli-veries per year. According to the hospital clinicalpractices, the women first came to an admissionroom where the labor progress was assessed, andwhere induction took place if deemed necessary. Thewomen in active labor, defined as cervical dilatation‡3 cm and the presence of regular uterine contrac-tions, were transferred to a labor room, and all thesewomen had spontaneously or artificially rupturedmembranes. All women labored in the same roomand external companions were therefore notallowed. The women were assisted by obstetriciansor medical students. During the study period, thefollowing forms of pain relief were available:Tramadol (Tramadol�, 100 mg i.m.); pentazocine/

promethazine (Fortwin/Phenergan�, 30–60 mg/25–50 mg i.m.) and morphine/promethazine (Morphine/Phenergan�, 3.5–7 mg i.m. or i.v./25–50 mg i.m.).The women were eligible for the study if they were

in active labor and had been transferred to the laborroom with a cervical dilatation between 3 and 7 cm.They had to be healthy with an uncomplicated preg-nancy, nulliparous, at term, and carrying a live fetus inhead presentation. Exclusion criteria were: hyperten-sive disorder, preeclampsia, diabetes, neuropathicpain multiparity, intrauterine death, multiple fetuses,breech presentation, gestation <38 or >42 weeks,cervical dilatation <3 cm or >7 cm, elective cesareansection, and the presence of pharmacological painrelief. The most common exclusion criteria weremultiparity, followed by cervical dilatation >7 cm,and a medical disorder such as hypertension anddiabetes.The screening for eligibility took place between

8 am and 1 pm, Monday to Saturday except forholidays, and was performed by two obstetricians.The social worker who also collected the data, pro-vided the eligible women with information about theaim of the study, i.e. to evaluate the effect of acupres-sure on labor pain. If they agreed to participate theywere randomly assigned to receive either treatmentwith acupressure or standard care without acupres-sure. The women who gave written consent wererandomly assigned to one of three groups as describedbelow.The study was approved by the Human Ethical

Committee at the Medical College in Trivandrum(reg. nr. C20/EC05/07/MCT) and the Regional Eth-ical Committee in Stockholm, Sweden (reg. nr. 2007/1190). The study is registered in Karolinska Clinicalstudy registry (ID: CT20090020).A computerized program was used to allocate the

participants to one of the treatment groups, i.e. acu-pressure group (APG), touch group (TG) or standardcare group (SCG) under investigation. A paper stripwith one of the letter combinations APG, TG orSCG was put in consecutively numbered sealed opa-que envelops. The women in the APG were treatedwith acupressure at acupuncture point SP6 on bothlegs simultaneously during each contraction over aperiod of 30 minutes. This treatment was repeatedafter 2 hours if the woman had not entered secondstage labor or been delivered. SP6 is located fourfingers width, measured with the woman’s ownfingers, above the tip of medial malleoulus at theposterior border of tibia. The intensity of pressurewas adapted to reach each woman’s pain threshold.Women in the TG received light touch, without anypressure, at acupoint SP6 on both legs during con-tractions over a 30-minute period. The reason for

1454 A. Hjelmstedt et al.

including this group was to control for the possibleeffects of the presence of a person paying particularattention to the woman. The TG was identical to theAPG, except for the pressure. For the sake of brevity,touch is referred to as ‘treatment’ in the following text.Women in the SCG received standard care with noacupressure or touch. The acupressure and touchwere performed by one and the same person whohad undergone 3 days of training by a certificatedacupressure therapist. The training included theoryand practical training.After obtaining written consent and before ran-

domization, baseline information was collected byinterviewing the women. Questions about thewomen’s sociodemographic background were prede-fined with given response alternatives. The women’sresponses were entered into a questionnaire by asocial worker trained in data collection.Women in the APG and the TG were asked to rate

pain intensity on a 100-mm visual analog scale (VAS)anchored from ‘no pain at all’ to ‘much more painthan I could imagine’. Ratings were performed priorto treatment, immediately after treatment, and 30,60 and 120 minutes after treatment. Women in theSCG rated their labor pain at the correspondingpoints of time as in the APG and the TG.After delivery (2–24 hours) on the postnatal ward,

VASs were used to rate memory of labor pain, abilityto cope with labor pain (‘not at all’ to ‘very well’), andoverall experience of childbirth (‘very bad’ to ‘verygood’). Women used a pencil to put a mark on therespective line. Medical data from hospital recordswere collected by two obstetricians.The data collector was blinded to the patient’s

group allocation. However, in few cases there wasmore than one woman in the study in the labor roomat the same time and the data collector could thenhave noted that another woman was being treated.She could not see a difference between the womenwho were treated by acupressure (APG) and touch(TG) since these treatments looked the same from anobserver’s point of view, but she could conclude thatthis was not a woman in the SCG.

Statistical analyses

Power was estimated on the principal outcome, i.e.the women’s assessment of in-labor pain, and basedon the results from the acupressure study by Lee et al.where the women’s experience of pain had beenmeasured on a VAS (2). They compared the painscores of 36 women who received acupressure withthose of the 39 women who received ‘touch’ at60 minutes after the intervention and found a

significant difference (p < 0.01, power 80%) of12 mm. We aimed at detecting a similar differencebut extended our sample to 70 women per group inorder to account for drop-outs caused by the longerduration of the follow-up.Data are presented as numbers or mean and stan-

dard deviation (SD). Groups were compared regard-ing differences in labor pain intensity at different timeintervals after treatment, compared with the baselineassessment, by means of one-way analyses of variance(ANOVA) followed by post hoc Bonferroni tests toavoid Type 1 errors. Regarding the postnatal assess-ments, the differences between groups in VAS scoresof labor pain, coping ability and overall experience ofchildbirth were analyzed by means of ANOVA fol-lowed by post hoc Bonferroni tests.Statistical significance was defined as p < 0.05.

Statistical analyses were carried out using the SPSSversion 15.0.

Results

The flowchart of participants in the study is presentedin Figure 1. Out of 773 women assessed for eligibility,227 met the inclusion criteria. Fourteen declined toparticipate and those who remained were randomizedto APG (n = 71), TG (n = 71) and SCG (n = 71). Onewoman in the SCG withdrew after randomization.Table 1 shows that the women in each group hadsimilar sociodemographic and obstetric backgrounds.On average, they were young and fairly well-educated.Gestational age was, on average, 39 weeks in all threegroups. Induction rates were 32% in APG, 29% inTG and 26% in SCG. Cervical dilatation beforerandomization was around 3.5 cm in all groups. Inspite of pharmacological pain relief being an exclusioncriterion in the study, some women in each groupreceived either Tramadol�, Fortwin/Phenergan� orMorphin/Phenergan� before randomization. Thiswas a deviation from the trial protocol which willbe further discussed below.The mean (SD) pain scores at baseline were:

62.6 (14.9) in APG, 57.5 (15.9) in TG and56.7 (16.6) in SCG. Since the difference betweenAPG and SCG baseline scores was significant(p < 0.05), and the difference between APG andTG was bordering on significance (p = 0.05), wechose to compare labor pain intensity at differenttime intervals after treatment with the baseline assess-ment as previously described. Figure 2 shows changesin pain scores expressed as the mean differencebetween the baseline assessment and the follow-up assessments in respective groups. Some womengave birth shortly after treatment (corresponding time

Acupressure to reduce labor pain 1455

in SCG) or before the end of the last pain assessmentscheduled at 120 minutes after treatment. As a con-sequence the number of women differed in theseanalyses. During the observation period, which lastedfor 2.5 hours (30 minutes treatment + 120 minutesfollow-up), contractions became more intense, andwithout any pain relief one would therefore expect thewomen’s pain scores to increase accordingly. Thiswas also the case in the SCG in which the differencefrom the baseline assessment increased continuously.This was also found in the TG. By contrast, a reduc-tion of pain was observed in the APG and was mostapparent when comparing baseline with immediatelyafter treatment measures. There were significant dif-ferences between the APG and the SCG as well asbetween the APG and the TG with respect to differ-ence in pain scores between the baseline assessmentand the follow-up assessments (immediately, 30,

60 and 120 minutes after treatment) but no suchdifferences were found between the TG and theSCG (Figure 2). When the women who had receivedpharmacological pain relief prior to treatment (APG:9; TG: 8; SCG: 11) were excluded from the analyses,the overall results did not change.Even though the APG had higher pain scores at

baseline, the mean (SD) pain scores in the SCG weresignificantly higher in comparison to the APG at allfollow-up assessments (30, 60 and 120 minutes aftertreatment, p < 0.05) except immediately after treat-ment. At all follow-up assessments, there were non-significantly higher mean pain ratings in the TG incomparison to the APG, and in the SCG in compar-ison to the TG.Only 22 women in the APG, 26 in the TG and

23 in the SCG were in labor long enough afterthe second treatment to be able to complete all

EnrollmentAssessed for eligility (n = 773)

Excluded (n = 560)• Not meeting inclusioncriteria (n = 546)• Declined participation (n = 14)

Randomized (n = 213)

Allocation Allocated to APG (n = 71)• Received APG (n = 71)

Allocated to TG (n = 71)• Received TG (n = 71)

Allocated to SCG (n = 71)• Received SCG (n = 70)• Withdraw (n = 1)

Follow-Up Lost to follow-up (n = 0) Lost to follow-up (n = 0) Lost to follow-up (n = 0)

Analysis Analyzed (n = 71) Analyzed (n = 71) Analyzed (n = 70)

Figure 1. Flow chart of participants in trial.Note: APG, acupressure group; TG, touch group; SCG, standard care group.

Table 1. Sociodemographic and obstetric characteristics of the women in the randomized groups.

APG (n = 71) TG (n = 71) SCG (n = 70)

Sociodemographic dataAge, years, mean (SD) 22.4 (2.7) 22.7 (2.9) 22.9 (3.4)Education, years, mean (SD) 12.4 (2.4) 12.0 (2.6) 11.6 (2.8)

Obstetric dataInduction, n 32 29 26Prostaglandin 31 28 26Oxytocin 1 1 0

Gestational age, weeks, mean (SD) 38.7 (1.3) 38.7 (0.8) 38.6 (0.8)Cervical dilatation before randomization, cm, mean (SD) 3.6 (0.9) 3.5 (1.0) 3.4 (0.7)Pharmacological pain relief before randomizationa, n 9 8 11

aTramadol�, Fortwin/Phenergan� or Morphine/Phenergan�.Note: APG, acupressure group; TG, touch group; SCG, standard care group.


pain-ratings. This reduced sample was not largeenough to allow for the assessment of the effect ofthe second treatment.Table 2 shows that labor outcomes were similar in

each study group. About half of the women receivedoxytocin for augmentation and pharmacological painrelief (either after or before inclusion into the study).The proportions of women who had received phar-macological pain relief during labor were equallydistributed between the groups (APG 49%, TG48%, SCG 57%). More women in the APG had aspontaneous vaginal delivery compared with the othertwo groups, but this difference was not significant.

The majority had an episiotomy (89% in APG; 75%in TG; 85% in SCG), reflecting clinical practices inthe hospital. Infant birth weight and length was similarin each group. Mean Apgar score at 5 minutes was9.6. One infant in the APG had an Apgar score of 6 at5 minutes but recovered from the respiratory distresssoon after birth.Retrospectively (2–24 hours after birth), the women

in the APG remembered having had less pain duringlabor and said they coped better with their labor paincompared with the SCG (Table 3). Compared to thewomen in the TG, those in the APG rememberedhaving coped better with the pain. There were no

4.0 (10.8)n = 62

8.6 (11.6)n = 55

9.4 (13.1)n = 39

4.7 (10.8)n = 69

8.3 (9.6)n = 60

11.9 (11.5)n = 50

13.4 (14.7)n = 40

6

8

10

12

14

16

–4.4 (8.1)n = 69

–2.8 (11.6)n = 56

1.1 (14.0)n = 52

–0.2 (15.4)n = 39

2.0 (8.5)n = 68

–6

–4

–2

0

2

4

VA

S s

core

dif

fere

nce

, mea

n (

SD

)

APG TG SCG

Immediately 30 minutes 60 minutes 120 minutes

Time after first treatment

Figure 2. Assessment of in-labor pain at different time intervals after treatment compared with before treatment.Note: APG, acupressure group; TG, touch group; SCG, standard care group.

Table 2. Labor data in the randomized groups.

APG (n = 71) TG (n = 71) SCG (n = 70)

Oxytocin for augmentation, n 38 37 38Pharmacological pain relief during labora, n 35 34 40Spontaneous vaginal delivery, n 55 43 47Emergency cesarean delivery, n 7 17 12Forceps, n 1 3 4Vacuum extraction, n 8 8 7Episiotomy, n 63 53 59Infant birth weight, mean (SD) 2,981.1 (340.0) 2,931.8 (379.9) 2,941.5 (387.8)Infant birth length, mean (SD) 50.1 (0.4) 50.2 (0.7) 50.2 (0.6)Apgar 5 minutes, mean (SD) 9.6 (0.6) 9.6 (0.5) 9.7 (0.5)

aTramadol�, Fortwin/Phenergan� or Morphine/Phenergan�.Note: APG, acupressure group; TG, touch group; SCG, standard care group.


statistical differences between the groups regardingthe overall experience of childbirth.

Discussion

We found that acupressure on acupoint SP6 duringcontractions reduced the experience of pain intensityin nulliparous women during the active phase oflabor, whereas pain intensity increased in womenwho received light touch or standard care. The effectof acupressure was most apparent immediately aftertreatment but the difference in pain scores comparedwith the group receiving only touch and the groupreceiving no form of treatment lasted for at least2 hours. At this point in time the women’s pain scoresreached about the same level as before treatment, inspite of the progression of labor over a period of2.5 hours. Considering that there was an imbalancein pain intensity pain scores at baseline between thegroups we chose to calculate mean differences in laborpain intensity between the baseline assessment andthe follow-up assessments. Despite this initial differ-ence, significantly higher mean pain ratings wereobserved in the SCG in comparison to the APG atall follow-up assessments except immediately afterthe treatment. Similarly, the TG showed numericallyhigher pain ratings as compared to the APG at follow-up assessments, but these differences were not statis-tically different. Thus, a positive treatment effect ofacupressure in the active phase of labor in nulliparouswomen was indicated. Furthermore, this study indi-cates that acupressure may affect women’s retrospec-tive assessment of labor pain, since the women in theAPG remembered having had less pain than thewomen in the SCG, and were better able to copewith the pain than the women in the SCG and the TG,when asked after the birth. Since the proportions ofwomen who had received pharmacological pain reliefduring labor were equally distributed between thegroups it is not probable that this could have affected

the results (APG 49%, TG 48%, SCG 57%). Ourfindings support the conclusion of previous studiesthat acupressure is effective in reducing laborpain (2,3).The effect of acupressure remains unclear on a

mechanistic level. One explanation is based on thegate-control theory (6). According to this theoryacupressure activates mechanoreceptors that inner-vate sensory nerve fibers, A-beta and/or A-deltadepending on the pressure intensity, which leads tothe inhibition of pain transmission at the spinal level.It is also possible that acupressure activates centralpain inhibitory centers, leading to an activation of thedescending pain inhibitory pathways (7). However, itcannot be ruled out that the positive effect thatwe found in the APG could be due to expectationsof pain relief, thus driving a placebo elicited inhibitionof pain.The reason for including a group of women who

received touch without pressure was to control for thepossible effects of the presence of a person payingparticular attention to the woman. A Cochrane reviewhas shown that continuous support during labor mayreduce the use of obstetric pain relief and increasesatisfaction with childbirth (8). Although Figure 2suggests that the women in the TG experiencedless pain than the women in the SCG, this differencewas not statistically significant. Neither did we findany difference in the postnatal assessment of child-birth between these two groups.A strength of our study was that the risk of selection

bias was limited. All the women who had been trans-ferred to the labor room with a cervical dilatationbetween 3 and 7 cm during the data collection periodwere screened for eligibility and only one womanchose to withdraw after randomization. A limitationof the study was that blinding to the respectivegroup was not possible. The women who receivedneither acupressure nor touch could conclude thatthey had received no treatment. However, the differ-ence between acupressure and touch was less

Table 3. Postnatal assessments of labor pain, ability to cope with labor pain and overall experience expressed as mean values on visual analogscale (VAS).

VAS score (0–100 mm)

APG(n = 71)

Mean (SD)

TG(n = 71)

SCG(n = 70)

Mean (SD) paAPG vs. SCG

pbAPG vs. TG

pbTG vs. SCG

pb

Labor pain 74.0 (18.2) 78.9 (19.9) 84.3 (15.8) 0.004 0.003 0.34 0.23Coping with labor pain 90.1 (15.9) 82.3 (19.7) 79.2 (20.2) 0.002 0.002 0.04 1.0Experience of childbirth 85.0 (25.0) 84.3 (22.8) 76.2 (25.2) 0.06 0.1 1.0 0.15

Labor pain: 0, no pain at all; 100, much more pain than I could think of. Ability to cope with labor pain: 0, not at all; 100, very well. Experienceof labor: 0, very poor; 100, very good.aANOVA.bBonferroni test.Note: APG, acupressure group; TG, touch group; SCG, standard care group.


obvious, and we believe that most of the women werenot aware of the difference. They had been informedthat the aim of the study was to evaluate the effect ofacupressure on labor pain, but no details were givenabout the procedures. From the clinicians’ and thedata collector’s perspective the two treatments lookedthe same.In conclusion, our study shows that acupressure

seems to reduce pain during the active phase of laborin nulliparous women giving birth in a context wheresocial support and epidural analgesia are not available.However, the treatment effect is small which suggeststhat acupressure may be most effective during theinitial phase of labor. In contexts where more effectivemethods of pain relief are available, such as epiduralanalgesia, acupressure may be an alternative predom-inantly in early labor. In contexts where resources arelimited acupressure could be an important option forwomen with painful labor pain. Acupressure is notassociated with risks of infections since the skin isnot penetrated by needles, and there are no costs forequipment. In addition, acupressure is easy toadminister and extensive training of the person whoadministers the treatment is not necessary. However,further studies of efficacy as well as effectiveness areneeded to determine the clinical applicability ofacupressure in labor pain.

Acknowledgements

We are grateful to Manju Chandrika Soman foracupressure and touch treatments, Aseena

Naseemabeevi and Vrinda Menon for data collec-tion and K.T. Shenoy for advice on study designand analysis of data. The study was funded by theOsher Center for Integrative Medicine, KarolinskaInstitutet and the Center for Health Care Science,Karolinska Institutet.

Declaration of interest: The authors report noconflicts of interest. The authors alone are responsiblefor the content and writing of the paper.

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acupressure to reduce labor pain

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