Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in polycystic ovary syndrome

BACKGROUND

Metformin has been proposed as possibly a safer and more effective long-term treatment than the oral contraceptive pill (OCP) in women with polycystic ovary syndrome (PCOS). It is important to directly compare the efficacy and safety of metformin versus OCP in the long-term treatment of women with PCOS. This is an update of a Cochrane Review comparing insulin sensitising agents with the OCP and only includes studies on metformin.

OBJECTIVES

To assess the effectiveness and safety of metformin versus the OCP (alone or in combination) in improving clinical, hormonal, and metabolic features of PCOS.

SEARCH METHODS

In August 2019 we searched the Cochrane Gynaecology and Fertility Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase and CINAHL, the trial registers, handsearched references of the identified articles, and contacted experts in the field to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of the use of metformin versus the OCP (alone or in combination) for women with PCOS.

DATA COLLECTION AND ANALYSIS

We used standard methods recommended by Cochrane. The primary review outcomes were the clinical parameters of hirsutism and adverse events, both severe (requiring stopping of medication), and minor. In the presence of substantial heterogeneity (I² statistic > 50), which could be explained by pre-specified subgroup analyses on the basis of BMI, we reported the subgroups separately.

MAIN RESULTS

This is a substantive update. We identified 38 additional studies. We included 44 RCTs (2253 women), which comprised 39 RCTs on adult women (2047 women) and five RCTs on adolescent women (206 women). Evidence quality ranged from very low to low. The main limitations were risk of bias, imprecision and inconsistency. Metformin versus the OCP In adult women, we are uncertain of the effect of metformin compared to the OCP on hirsutism in subgroup body mass index (BMI) < 25 kg/m² (mean difference (MD) 0.38, 95% confidence interval (CI) -0.44 to 1.19, 3 RCTs, n = 134, I² = 50%, very low-quality evidence) and subgroup BMI > 30 kg/m² (MD -0.38, 95% CI -1.93 to 1.17; 2 RCTs, n = 85, I² = 34%, low-quality evidence). Metformin may be less effective in improving hirsutism compared to the OCP in the subgroup BMI 25 kg/m² to 30 kg/m² (MD 1.92, 95% CI 1.21 to 2.64, 5 RCTs, n = 254, I² = 0%, low-quality evidence). Metformin may increase severe gastro-intestinal adverse events rate compared to the OCP (Peto odds ratio (OR) 6.42, 95% CI 2.98 to 13.84, 11 RCTs, n = 602, I² = 0%, low-quality evidence). Metformin may decrease the incidence of severe other adverse events compared to the OCP (Peto OR 0.20, 95% CI 0.09 to 0.44, 8 RCTs, n = 363, I² = 0%, low-quality evidence). There were no trials reporting on minor adverse events. In adolescents, we are uncertain whether there is a difference between Metformin and the OCP, on hirsutism and adverse events. Metformin versus metformin combined with the OCP In adult women, metformin may be less effective in improving hirsutism compared to Metformin combined with the OCP (MD 1.36, 95% CI 0.62 to 2.11, 3 RCTs, n = 135, I²= 9%, low-quality evidence). We are uncertain if there was a difference between metformin and metformin combined with the OCP for severe gastro-intestinal adverse events (OR 0.74, 95% CI 0.21 to 2.53, 3 RCTs, n = 171, I² = 0%, low-quality evidence), or for severe other adverse events (OR 0.56, 95% CI 0.11 to 2.82, 2 RCTs, n = 109, I² = 44%, low-quality evidence). There were no trials reporting on minor adverse events. In adolescents, there were no trials for this comparison. The OCP versus metformin combined with the OCP In adult women, the OCP may be less effective in improving hirsutism compared to metformin combined with the OCP (MD 0.54, 95% CI 0.20 to 0.89, 6 RCTs, n = 389, I²= 1%, low-quality evidence). The OCP may decrease the incidence of severe gastro-intestinal adverse events compared to metformin combined with the OCP (OR 0.20, 95% CI 0.06 to 0.72, 5 RCTs, n = 228, I² = 0%, low-quality evidence). We are uncertain if there is a difference between the OCP and metformin combined with the OCP for severe other adverse events (OR 1.61, 95% CI 0.49 to 5.37, 4 RCTs, n = 159, I² = 12%, low-quality evidence). The OCP may decrease the incidence of minor (gastro-intestinal) adverse events compared to metformin combined with the OCP (OR 0.06, 95% CI 0.01 to 0.44, 2 RCTs, n = 98, I² = 0%, low-quality evidence). In adolescents, we are uncertain whether there is a difference between the OCP, compared to metformin combined with the OCP, on hirsutism or adverse events.

AUTHORS' CONCLUSIONS

In adult women with PCOS, metformin may be less effective in improving hirsutism compared to the OCP in the subgroup BMI 25 kg/m² to 30 kg/m² but we are uncertain if there was a difference between metformin and the OCP in subgroups BMI < 25 kg/m² and BMI > 30kg/m². Compared to the OCP, metformin may increase the incidence of severe gastro-intestinal adverse events and decrease the incidence of severe other adverse events with no trials reporting on minor adverse events. Either metformin alone or the OCP alone may be less effective in improving hirsutism compared to metformin combined with the OCP. We are uncertain whether there is a difference between the OCP alone and metformin alone compared to metformin combined with the OCP for severe or minor adverse events except for the OCP versus metformin combined with the OCP where the OCP may decrease the incidence of severe and minor gastro-intestinal adverse events. In adolescent women with PCOS, we are uncertain whether there is a difference between any of the comparisons for hirsutism and adverse events due to either no evidence or very low-quality evidence. Further large well-designed RCTs that stratify for BMI are needed to evaluate metformin versus the OCP and combinations in women with PCOS, in particular adolescent women.

Exercise for dysmenorrhoea

BACKGROUND

Exercise has a number of health benefits and has been recommended as a treatment for primary dysmenorrhoea (period pain), but the evidence for its effectiveness on primary dysmenorrhoea is unclear. This review examined the available evidence supporting the use of exercise to treat primary dysmenorrhoea.

OBJECTIVES

To evaluate the effectiveness and safety of exercise for women with primary dysmenorrhoea.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility specialised register, CENTRAL, MEDLINE, Embase, PsycINFO, AMED and CINAHL (from inception to July 2019). We searched two clinical trial databases (inception to March 2019) and handsearched reference lists and previous systematic reviews.

SELECTION CRITERIA

We included studies if they randomised women with moderate-to-severe primary dysmenorrhoea to receive exercise versus no treatment, attention control, non-steroidal anti-inflammatory drugs (NSAIDs) or the oral contraceptive pill. Cross-over studies and cluster-randomised trials were not eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected the studies, assessed eligible studies for risk of bias, and extracted data from each study. We contacted study authors for missing information. We assessed the quality of the evidence using GRADE. Our primary outcomes were menstrual pain intensity and adverse events. Secondary outcomes included overall menstrual symptoms, usage of rescue analgesic medication, restriction of daily life activities, absence from work or school and quality of life.

MAIN RESULTS

We included a total of 12 trials with 854 women in the review, with 10 trials and 754 women in the meta-analysis. Nine of the 10 studies compared exercise with no treatment, and one study compared exercise with NSAIDs. No studies compared exercise with attention control or with the oral contraceptive pill. Studies used low-intensity exercise (stretching, core strengthening or yoga) or high-intensity exercise (Zumba or aerobic training); none of the included studies used resistance training.Exercise versus no treatmentExercise may have a large effect on reducing menstrual pain intensity compared to no exercise (standard mean difference (SMD) -1.86, 95% confidence interval (CI) -2.06 to -1.66; 9 randomised controlled trials (RCTs), n = 632; I²= 91%; low-quality evidence). This SMD corresponds to a 25 mm reduction on a 100 mm visual analogue scale (VAS) and is likely to be clinically significant. We are uncertain if there is any difference in adverse event rates between exercise and no treatment.We are uncertain if exercise reduces overall menstrual symptoms (as measured by the Moos Menstrual Distress Questionnaire (MMDQ)), such as back pain or fatigue compared to no treatment (mean difference (MD) -33.16, 95% CI -40.45 to -25.87; 1 RCT, n = 120; very low-quality evidence), or improves mental quality of life (MD 4.40, 95% CI 1.59 to 7.21; 1 RCT, n = 55; very low-quality evidence) or physical quality of life (as measured by the 12-Item Short Form Health Survey (SF-12)) compared to no exercise (MD 3.40, 95% CI -1.68 to 8.48; 1 RCT, n = 55; very low-quality evidence) when compared to no treatment. No studies reported on any changes in restriction of daily life activities or on absence from work or school.Exercise versus NSAIDsWe are uncertain if exercise, when compared with mefenamic acid, reduced menstrual pain intensity (MD -7.40, 95% CI -8.36 to -6.44; 1 RCT, n = 122; very low-quality evidence), use of rescue analgesic medication (risk ratio (RR) 1.77, 95% CI 1.21 to 2.60; 1 RCT, n = 122; very low-quality evidence) or absence from work or school (RR 1.00, 95% CI 0.49 to 2.03; 1 RCT, n = 122; very low-quality evidence). None of the included studies reported on adverse events, overall menstrual symptoms, restriction of daily life activities or quality of life.

AUTHORS' CONCLUSIONS

The current low-quality evidence suggests that exercise, performed for about 45 to 60 minutes each time, three times per week or more, regardless of intensity, may provide a clinically significant reduction in menstrual pain intensity of around 25 mm on a 100 mm VAS. All studies used exercise regularly throughout the month, with some studies asking women not to exercise during menstruation. Given the overall health benefits of exercise, and the relatively low risk of side effects reported in the general population, women may consider using exercise, either alone or in conjunction with other modalities, such as NSAIDs, to manage menstrual pain. It is unclear if the benefits of exercise persist after regular exercise has stopped or if they are similar in women over the age of 25. Further research is required, using validated outcome measures, adequate blinding and suitable comparator groups reflecting current best practice or accounting for the extra attention given during exercise.

Acupuncture and acupressure for premenstrual syndrome

BACKGROUND

Acupuncture has a history of traditional use in China for women's health conditions including premenstrual syndrome (PMS), but its effectiveness for this condition remains unclear. This review examined the available evidence supporting the use of acupuncture or acupressure to treat PMS.

OBJECTIVES

To evaluate the effectiveness and safety of acupuncture or acupressure for women with PMS or premenstrual dysphoric disorder (PMDD).

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility Specialised Register, Cochrane Central Register of Studies Online (CENTRAL CRSO), MEDLINE, Embase, AMED, PsycINFO, CINAHL (from inception to 21 September 2017), two clinical trial databases (from their inception to 21 September 2017), and four electronic databases in China (from their inception to 15 October 2017): Chinese Biomedical Literature database (CBM), China National Knowledge Infrastructure (CNKI), VIP information/ Chinese Scientific Journals database and WANFANG. Reference lists from included articles were handsearched.

SELECTION CRITERIA

We included studies if they randomised women with PMS and associated disorders (PMDD and late luteal phase dysphoric disorder/LPDD) to receive acupuncture or acupressure versus sham, usual care/waiting-list control or pharmaceutical interventions mentioned by the International Society for Premenstrual Disorders (ISPMD). If acupuncture or acupressure were combined with another therapy, these studies were also included where the additional therapy was the same in both groups. Cross-over studies were eligible for inclusion, but only data from the first phase could be used.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected the studies, assessed eligible studies for risk of bias, and extracted data from each study. Study authors were contacted for missing information. The quality of the evidence was assessed using GRADE. Our primary outcomes were overall premenstrual symptoms and adverse events. Secondary outcomes included specific PMS symptoms, response rate and quality of life.

MAIN RESULTS

Five trials (277 women) were included in this review. No trials compared acupuncture or acupressure versus other active treatments. The number of treatment sessions ranged from seven to 28. The quality of the evidence ranged from low to very low quality, the main limitations being imprecision due to small sample sizes and risk of bias related to detection bias and selective reporting.Acupuncture versus sham acupunctureAcupuncture may provide a greater reduction in mood-related PMS symptoms (mean difference (MD) -9.03, 95% confidence interval (CI) -10.71 to -7.35, one randomised controlled trial (RCT), n = 67, low-quality evidence) and in physical PMS symptoms (MD -9.11, 95% CI -10.82 to -7.40, one RCT, n = 67, low-quality evidence) than sham acupuncture, as measured by the Daily Record of Severity of Problems scale (DRSP). The evidence suggests that if women have a mood score of 51.91 points with sham acupuncture, their score with acupuncture would be between 10.71 and 7.35 points lower and if women have a physical score of 46.11 points, their score with acupuncture would be between 10.82 and 7.4 points lower.There was insufficient evidence to determine whether there was any difference between the groups in the rate of adverse events (risk ratio (RR) 1.74, 95% CI 0.39 to 7.76, three RCTs, n = 167, I² = 0%, very low-quality evidence).Specific PMS symptoms were not reportedThere may be little or no difference between the groups in response rates. Use of a fixed-effect model suggested a higher response rate in the acupuncture group than in the sham group (RR 2.59, 95% CI 1.71 to 3.92; participants = 100; studies = 2; I² = 82%), but owing to the high heterogeneity we tested the effect of using a random-effects model, which provided no clear evidence of benefit for acupuncture (RR 4.22, 95% CI 0.45 to 39.88, two RCTs, n = 100, I² = 82%, very low-quality evidence).Acupuncture may improve quality of life (measured by the WHOQOL-BREF) compared to sham (MD 2.85, 95% CI 1.47 to 4.23, one RCT, n = 67, low-quality evidence).Acupuncture versus no treatmentDue to the very low quality of the evidence, we are uncertain whether acupuncture reduces PMS symptoms compared to a no treatment control (MD -13.60, 95% CI -15.70 to -11.50, one RCT, n = 14).No adverse events were reported in either group.No data were available on specific PMS symptoms, response rate or quality of life outcomes.Acupressure versus sham acupressureWe found low-quality evidence that acupressure may reduce the number of women with moderate to severe PMS symptoms at the end of the trial compared to sham acupressure (RR 0.64 95% CI 0.52 to 0.79, one RCT, n = 90, low-quality evidence). The evidence suggests that if 97 women out of 100 in the sham acupressure group had moderate to severe PMS symptoms, the number of women in the acupressure group with moderate to severe symptoms would be 50 to 76 women.Acupressure may improve both physical (MD 24.3, 95% CI 17.18 to 31.42, one RCT, n = 90, low-quality evidence) and mental (MD 17.17, 95% CI 13.08 to 21.26, one RCT, n = 90, low-quality evidence) quality of life.No data were available on adverse events, specific symptoms or response rates.

AUTHORS' CONCLUSIONS

The limited evidence available suggests that acupuncture and acupressure may improve both physical and psychological symptoms of PMS when compared to a sham control. There was insufficient evidence to determine whether there was a difference between the groups in rates of adverse events.There is no evidence comparing acupuncture or acupressure versus current ISPMD recommended treatments for PMS such as selective serotonin reuptake inhibitors (SSRIs). Further research is required, using validated outcome measures for PMS, adequate blinding and suitable comparator groups reflecting current best practice.

Massage, reflexology and other manual methods for pain management in labour

BACKGROUND

Many women would like to avoid pharmacological or invasive methods of pain management in labour, and this may contribute towards the popularity of complementary methods of pain management. This review examined the evidence currently available on manual methods, including massage and reflexology, for pain management in labour. This review is an update of the review first published in 2012.

OBJECTIVES

To assess the effect, safety and acceptability of massage, reflexology and other manual methods to manage pain in labour.

SEARCH METHODS

For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register (30 June 2017), the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 6), MEDLINE (1966 to 30 June 2017, CINAHL (1980 to 30 June 2017), the Australian New Zealand Clinical Trials Registry (4 August 2017), Chinese Clinical Trial Registry (4 August 2017), ClinicalTrials.gov, (4 August 2017), the National Center for Complementary and Integrative Health (4 August 2017), the WHO International Clinical Trials Registry Platform (ICTRP) (4 August 2017) and reference lists of retrieved trials.

SELECTION CRITERIA

We included randomised controlled trials comparing manual methods with standard care, other non-pharmacological forms of pain management in labour, no treatment or placebo. We searched for trials of the following modalities: massage, warm packs, thermal manual methods, reflexology, chiropractic, osteopathy, musculo-skeletal manipulation, deep tissue massage, neuro-muscular therapy, shiatsu, tuina, trigger point therapy, myotherapy and zero balancing. We excluded trials for pain management relating to hypnosis, aromatherapy, acupuncture and acupressure; these are included in other Cochrane reviews.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality, extracted data and checked data for accuracy. We contacted trial authors for additional information. We assessed the quality of the evidence using the GRADE approach.

MAIN RESULTS

We included a total of 14 trials; 10 of these (1055 women) contributed data to meta-analysis. Four trials, involving 274 women, met our inclusion criteria but did not contribute data to the review. Over half the trials had a low risk of bias for random sequence generation and attrition bias. The majority of trials had a high risk of performance bias and detection bias, and an unclear risk of reporting bias. We found no trials examining the effectiveness of reflexology.MassageWe found low-quality evidence that massage provided a greater reduction in pain intensity (measured using self-reported pain scales) than usual care during the first stage of labour (standardised mean difference (SMD) -0.81, 95% confidence interval (CI) -1.06 to -0.56, six trials, 362 women). Two trials reported on pain intensity during the second and third stages of labour, and there was evidence of a reduction in pain scores in favour of massage (SMD -0.98, 95% CI -2.23 to 0.26, 124 women; and SMD -1.03, 95% CI -2.17 to 0.11, 122 women). There was very low-quality evidence showing no clear benefit of massage over usual care for the length of labour (in minutes) (mean difference (MD) 20.64, 95% CI -58.24 to 99.52, six trials, 514 women), and pharmacological pain relief (average risk ratio (RR) 0.81, 95% CI 0.37 to 1.74, four trials, 105 women). There was very low-quality evidence showing no clear benefit of massage for assisted vaginal birth (average RR 0.71, 95% CI 0.44 to 1.13, four trials, 368 women) and caesarean section (RR 0.75, 95% CI 0.51 to 1.09, six trials, 514 women). One trial reported less anxiety during the first stage of labour for women receiving massage (MD -16.27, 95% CI -27.03 to -5.51, 60 women). One trial found an increased sense of control from massage (MD 14.05, 95% CI 3.77 to 24.33, 124 women, low-quality evidence). Two trials examining satisfaction with the childbirth experience reported data on different scales; both found more satisfaction with massage, although the evidence was low quality in one study and very low in the other.Warm packsWe found very low-quality evidence for reduced pain (Visual Analogue Scale/VAS) in the first stage of labour (SMD -0.59, 95% CI -1.18 to -0.00, three trials, 191 women), and the second stage of labour (SMD -1.49, 95% CI -2.85 to -0.13, two trials, 128 women). Very low-quality evidence showed reduced length of labour (minutes) in the warm-pack group (MD -66.15, 95% CI -91.83 to -40.47; two trials; 128 women).Thermal manual methodsOne trial evaluated thermal manual methods versus usual care and found very low-quality evidence of reduced pain intensity during the first phase of labour for women receiving thermal methods (MD -1.44, 95% CI -2.24 to -0.65, one trial, 96 women). There was a reduction in the length of labour (minutes) (MD -78.24, 95% CI -118.75 to -37.73, one trial, 96 women, very low-quality evidence). There was no clear difference for assisted vaginal birth (very low-quality evidence). Results were similar for cold packs versus usual care, and intermittent hot and cold packs versus usual care, for pain intensity, length of labour and assisted vaginal birth.Music One trial that compared manual methods with music found very low-quality evidence of reduced pain intensity during labour in the massage group (RR 0.40, 95% CI 0.18 to 0.89, 101 women). There was no evidence of benefit for reduced use of pharmacological pain relief (RR 0.41, 95% CI 0.16 to 1.08, very low-quality evidence).Of the seven outcomes we assessed using GRADE, only pain intensity was reported in all comparisons. Satisfaction with the childbirth experience, sense of control, and caesarean section were rarely reported in any of the comparisons.

AUTHORS' CONCLUSIONS

Massage, warm pack and thermal manual methods may have a role in reducing pain, reducing length of labour and improving women's sense of control and emotional experience of labour, although the quality of evidence varies from low to very low and few trials reported on the key GRADE outcomes. Few trials reported on safety as an outcome. There is a need for further research to address these outcomes and to examine the effectiveness and efficacy of these manual methods for pain management.

Expectancy after the first treatment and response to acupuncture for menopausal hot flashes

Background

Evidence on the impact of expectancy on acupuncture treatment response is conflicting.

Objectives

This secondary analysis of a randomized sham-controlled trial on acupuncture for menopausal hot flashes investigated whether treatment expectancy score was associated with hot flash score at end-of-treatment. Secondary analyses investigated whether there were associations between other pre-specified factors and hot flash score.

Study design

Women experiencing moderately-severe hot flashes were randomized to receive 10 sessions of real or sham acupuncture over eight weeks. Hot flash score was collected using a seven-day hot flash diary, and expectancy using the modified Credibility and Expectancy Questionnaire immediately after the first treatment. Linear mixed-effects models with random intercepts were used to identify associations between expectancy score and hot flash score at end-of-treatment. Regression was also used to identify associations between pre-specified factors of interest and hot flash score. Because there was no difference between real and sham acupuncture for the primary outcome of hot flash score, both arms were combined in the analysis.

Results

285 women returned the Credibility and Expectancy Questionnaire, and 283 women completed both expectancy measures. We found no evidence for an association between expectancy and hot flash score at end-of-treatment for individual cases in either acupuncture or sham group. Hot flash scores at end-of-treatment were 8.1 (95%CI, 3.0 to 13.2; P = 0.002) points lower in regular smokers compared to those who had never smoked, equivalent to four fewer moderate hot flashes a day.

Conclusion

In our study of acupuncture for menopausal hot flashes, higher expectancy after the first treatment did not predict better treatment outcomes. Future research may focus on other determinants of outcomes in acupuncture such as therapist attention. The relationship between smoking and hot flashes is poorly understood and needs further exploration.

Acupuncture for pelvic and back pain in pregnancy: a systematic review

The objective of our study was to review the effectiveness of needle acupuncture in treating the common and disabling problem of pelvic and back pain in pregnancy. Two small trials on mixed pelvic/back pain and 1 large high-quality trial on pelvic pain met the inclusion criteria. Acupuncture, as an adjunct to standard treatment, was superior to standard treatment alone and physiotherapy in relieving mixed pelvic/back pain. Women with well-defined pelvic pain had greater relief of pain with a combination of acupuncture and standard treatment, compared to standard treatment alone or stabilizing exercises and standard treatment. We used a narrative synthesis due to significant clinical heterogeneity between trials. Few and minor adverse events were reported. We conclude that limited evidence supports acupuncture use in treating pregnancy-related pelvic and back pain. Additional high-quality trials are needed to test the existing promising evidence for this relatively safe and popular complementary therapy.