Average Risk Ratio Research Articles

Prophylactic oxytocin for the third stage of labour to prevent postpartum haemorrhage.

Prophylactic oxytocin for the third stage of labour to prevent postpartum haemorrhage.

Multiple-micronutrient supplementation for women during pregnancy.

Multiple-micronutrient supplementation for women during pregnancy.

Active versus expectant management for women in the third stage of labour.

Active versus expectant management for women in the third stage of labour.

Does Sustainability Affect Private Equity Asset Class?

In private equity industry ESG (Entrepreneurial, Social and Governance) metrics are gaining room, passing from the risk management process to influence the orientation of investment strategies. Motivations refer both to a firmer performance of the invested portfolios during the overall investment cycle and to a growing interest of fund subscribers in sustainable investments. Referring to the investment period from 2006 to 2015, we considered a sample of 126 PE investment vehicles. Amongst them 70 are ESG compliant (the main sample) and 56 are non-ESG. In terms of geographies we covered both Europe and North America. We have found that ESG funds generated more stable returns, in terms of net IRR standard deviation, in comparison with non-ESG vehicles, even if the latter showed a superior net IRR. This evidence is in favour of ESG funds as a more stable asset class in the medium-long period. Moreover, we have found that ESG funds contributed to a better portfolio diversification inside large institutional investors. In fact, their average Treynor Ratio is better than that figured out for non-ESG funds. The better performance didn’t depend on absolute returns, in fact the Sharpe Ratio was lower, but on a weaker dependence on the systematic risk as well as on a lower value for their total risk ratio. Finally, we have found that ESG funds were able to pursue a better risk hedging against sources of operating volatility, through a superior stability of their portfolios composition. Evidence was obtained comparing their average total risk ratio with that for the non-ESG funds. This research offers a valuable contribution to the literature on sustainable finance with a specific focus on private equity asset class.

Maternal position in the second stage of labour for women with epidural anaesthesia.

Maternal position in the second stage of labour for women with epidural anaesthesia.

Progestogen for preventing miscarriage in women with recurrent miscarriage of unclear etiology.

Progesterone, a female sex hormone, is known to induce secretory changes in the lining of the uterus essential for successful implantation of a fertilized egg. It has been suggested that a causative factor in many cases of miscarriage may be inadequate secretion of progesterone. Therefore, clinicians use progestogens (drugs that interact with the progesterone receptors), beginning in the first trimester of pregnancy, in an attempt to prevent spontaneous miscarriage. This is an update of a review, last published in 2013. To assess the efficacy and safety of progestogens as a preventative therapy against recurrent miscarriage. For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (6 July 2017) and reference lists from relevant articles, attempting to contact trial authors where necessary, and contacted experts in the field for unpublished works. Randomized or quasi-randomized controlled trials comparing progestogens with placebo or no treatment given in an effort to prevent miscarriage. Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. Two reviewers assessed the quality of the evidence using the GRADE approach. Thirteen trials (2556 women) met the inclusion criteria. Nine of the included trials compared treatment with placebo and the remaining four trials compared progestogen administration with no treatment. The trials were a mix of multicenter and single-center trials, conducted in Egypt, India, Jordan, UK and USA. In six trials women had had three or more consecutive miscarriages and in seven trials women had suffered two or more consecutive miscarriages. Routes, dosage and duration of progestogen treatment varied across the trials. The majority of trials were at low risk of bias for most domains. Eleven trials (2359 women) contributed data to the analyses.The meta-analysis of all women, suggests that there is probably a reduction in the number of miscarriages for women given progestogen supplementation compared to placebo/controls (average risk ratio (RR) 0.69, 95% confidence interval (CI) 0.51 to 0.92, 11 trials, 2359 women, moderate-quality evidence). A subgroup analysis comparing placebo-controlled versus non-placebo-controlled trials and different routes of administration showed no differences between subgroups for miscarriage. However, there appears to be a subgroup difference for miscarriage between women with three or more prior miscarriages compared to women with two or more miscarriages, with a more pronounced effect in women with three or more prior miscarriages. However, it should be noted that there was high heterogeneity in the subgroup of women with three or more prior miscarriages.None of the trials reported on any secondary maternal outcomes, including severity of morning sickness, thromboembolic events, depression, admission to a special care unit, or subsequent fertility.There was probably a slight benefit for women receiving progestogen seen in the outcome of live birth rate (RR 1.11, 95% CI 1.00 to 1.24, 7 trials, 2086 women, moderate-quality evidence). While the rate of preterm birth is probably reduced for women receiving progestogen, this outcome was mainly driven by one trial and thus should be interpreted with great caution (RR 0.59, 95% CI 0.39 to 0.89, 5 trials, 811 women, moderate-quality evidence). No clear differences were seen for women receiving progestogen for the other secondary outcomes of neonatal death or fetal genital abnormalities. A possible reduction in stillbirth was seen, but again this outcome was driven mainly by one trial and should be interpreted with caution (RR 0.38, 95% CI 0.24 to 0.58, 3 trials, 1199 women). There may be little or no difference in the rate of low birthweight and trials did not report on the secondary child outcomes of teratogenic effects or admission to a special care unit. For women with unexplained recurrent miscarriages, supplementation with progestogen therapy probably reduces the rate of miscarriage in subsequent pregnancies.

Interventionist versus expectant care for severe pre-eclampsia between 24 and 34 weeks' gestation.

Severe pre-eclampsia can cause significant mortality and morbidity for both mother and child, particularly when it occurs remote from term, between 24 and 34 weeks' gestation. The only known cure for this disease is delivery. Some obstetricians advocate early delivery to ensure that the development of serious maternal complications, such as eclampsia (fits) and kidney failure are prevented. Others prefer a more expectant approach, delaying delivery in an attempt to reduce the mortality and morbidity for the child that is associated with being born too early. To evaluate the comparative benefits and risks of a policy of early delivery by induction of labour or by caesarean section, after sufficient time has elapsed to administer corticosteroids, and allow them to take effect; with a policy of delaying delivery (expectant care) for women with severe pre-eclampsia between 24 and 34 weeks' gestation. For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) on 27 November 2017, and reference lists of retrieved studies. Randomised trials comparing the two intervention strategies for women with early onset, severe pre-eclampsia. Trials reported in an abstract were eligible for inclusion, as were cluster-trial designs. We excluded quasi-randomised trials. Three review authors independently assessed trials for inclusion and risk of bias, extracted data, and checked them for accuracy. We assessed the quality of the evidence for specified outcomes using the GRADE approach. We included six trials, with a total of 748 women in this review. All trials included women in whom there was no overriding indication for immediate delivery in the fetal or maternal interest. Half of the trials were at low risk of bias for methods of randomisation and allocation concealment; and four trials were at low risk for selective reporting. For most other domains, risk of bias was unclear. There were insufficient data for reliable conclusions about the comparative effects on most outcomes for the mother. Two studies reported on maternal deaths; neither study reported any deaths (two studies; 320 women; low-quality evidence). It was uncertain whether interventionist care reduced eclampsia (risk ratio (RR) 0.98, 95% confidence interval (CI) 0.06 to 15.58; two studies; 359 women) or pulmonary oedema (RR 0.45, 95% CI 0.07 to 3.00; two studies; 415 women), because the quality of the evidence for these outcomes was very low. Evidence from two studies suggested little or no clear difference between the interventionist and expectant care groups for HELLP (haemolysis, elevated liver enzymes, and low platelets) syndrome (RR 1.09, 95% CI 0.62 to 1.91; two studies; 359 women; low-quality evidence). No study reported on stroke. With the addition of data from two studies for this update, there was now evidence to suggest that interventionist care probably made little or no difference to the incidence of caesarean section (average RR 1.01, 95% CI 0.91 to 1.12; six studies; 745 women; Heterogeneity: Tau² = 0.01; I² = 63%).For the baby, there was insufficient evidence to draw reliable conclusions about the effects on perinatal deaths (RR 1.11, 95% CI 0.62 to 1.99; three studies; 343 women; low-quality evidence). Babies whose mothers had been allocated to the interventionist group had more intraventricular haemorrhage (RR 1.94, 95% CI 1.15 to 3.29; two studies; 537 women; moderate-quality evidence), more respiratory distress caused by hyaline membrane disease (RR 2.30, 95% CI 1.39 to 3.81; two studies; 133 women), required more ventilation (RR 1.50, 95% CI 1.11 to 2.02; two studies; 300 women), and were more likely to have a lower gestation at birth (mean difference (MD) -9.91 days, 95% CI -16.37 to -3.45 days; four studies; 425 women; Heterogeneity: Tau² = 31.74; I² = 76%). However, babies whose mothers had been allocated to the interventionist group were no more likely to be admitted to neonatal intensive care (average RR 1.19, 95% CI 0.89 to 1.60; three studies; 400 infants; Heterogeneity: Tau² = 0.05; I² = 84%). Babies born to mothers in the interventionist groups were more likely to have a longer stay in the neonatal intensive care unit (MD 7.38 days, 95% CI -0.45 to 15.20 days; three studies; 400 women; Heterogeneity: Tau² = 40.93, I² = 85%) and were less likely to be small-for-gestational age (RR 0.38, 95% CI 0.24 to 0.61; three studies; 400 women). There were no clear differences between the two strategies for any other outcomes. This review suggested that an expectant approach to the management of women with severe early onset pre-eclampsia may be associated with decreased morbidity for the baby. However, this evidence was based on data from only six trials. Further large, high-quality trials are needed to confirm or refute these findings, and establish if this approach is safe for the mother.

Calcium supplementation during pregnancy for preventing hypertensive disorders and related problems.

Calcium supplementation during pregnancy for preventing hypertensive disorders and related problems.

Discontinuation of intravenous oxytocin in the active phase of induced labour.

Discontinuation of intravenous oxytocin in the active phase of induced labour.

Treatments for women with gestational diabetes mellitus: an overview of Cochrane systematic reviews.

Successful treatments for gestational diabetes mellitus (GDM) have the potential to improve health outcomes for women with GDM and their babies. To provide a comprehensive synthesis of evidence from Cochrane systematic reviews of the benefits and harms associated with interventions for treating GDM on women and their babies. We searched the Cochrane Database of Systematic Reviews (5 January 2018) for reviews of treatment/management for women with GDM. Reviews of pregnant women with pre-existing diabetes were excluded.Two overview authors independently assessed reviews for inclusion, quality (AMSTAR; ROBIS), quality of evidence (GRADE), and extracted data. We included 14 reviews. Of these, 10 provided relevant high-quality and low-risk of bias data (AMSTAR and ROBIS) from 128 randomised controlled trials (RCTs), 27 comparisons, 17,984 women, 16,305 babies, and 1441 children. Evidence ranged from high- to very low-quality (GRADE). Only one effective intervention was found for treating women with GDM.EffectiveLifestyle versus usual careLifestyle intervention versus usual care probably reduces large-for-gestational age (risk ratio (RR) 0.60, 95% confidence interval (CI) 0.50 to 0.71; 6 RCTs, N = 2994; GRADE moderate-quality).PromisingNo evidence for any outcome for any comparison could be classified to this category.Ineffective or possibly harmful Lifestyle versus usual careLifestyle intervention versus usual care probably increases the risk of induction of labour (IOL) suggesting possible harm (average RR 1.20, 95% CI 0.99 to 1.46; 4 RCTs, N = 2699; GRADE moderate-quality).Exercise versus controlExercise intervention versus control for return to pre-pregnancy weight suggested ineffectiveness (body mass index, BMI) MD 0.11 kg/m², 95% CI -1.04 to 1.26; 3 RCTs, N = 254; GRADE moderate-quality).Insulin versus oral therapyInsulin intervention versus oral therapy probably increases the risk of IOL suggesting possible harm (RR 1.3, 95% CI 0.96 to 1.75; 3 RCTs, N = 348; GRADE moderate-quality).Probably ineffective or harmful interventionsInsulin versus oral therapyFor insulin compared to oral therapy there is probably an increased risk of the hypertensive disorders of pregnancy (RR 1.89, 95% CI 1.14 to 3.12; 4 RCTs, N = 1214; GRADE moderate-quality).InconclusiveLifestyle versus usual careThe evidence for childhood adiposity kg/m² (RR 0.91, 95% CI 0.75 to 1.11; 3 RCTs, N = 767; GRADE moderate-quality) and hypoglycaemia was inconclusive (average RR 0.99, 95% CI 0.65 to 1.52; 6 RCTs, N = 3000; GRADE moderate-quality).Exercise versus controlThe evidence for caesarean section (RR 0.86, 95% CI 0.63 to 1.16; 5 RCTs, N = 316; GRADE moderate quality) and perinatal death or serious morbidity composite was inconclusive (RR 0.56, 95% CI 0.12 to 2.61; 2 RCTs, N = 169; GRADE moderate-quality).Insulin versus oral therapyThe evidence for the following outcomes was inconclusive: pre-eclampsia (RR 1.14, 95% CI 0.86 to 1.52; 10 RCTs, N = 2060), caesarean section (RR 1.03, 95% CI 0.93 to 1.14; 17 RCTs, N = 1988), large-for-gestational age (average RR 1.01, 95% CI 0.76 to 1.35; 13 RCTs, N = 2352), and perinatal death or serious morbidity composite (RR 1.03; 95% CI 0.84 to 1.26; 2 RCTs, N = 760). GRADE assessment was moderate-quality for these outcomes.Insulin versus dietThe evidence for perinatal mortality was inconclusive (RR 0.74, 95% CI 0.41 to 1.33; 4 RCTs, N = 1137; GRADE moderate-quality).Insulin versus insulinThe evidence for insulin aspart versus lispro for risk of caesarean section was inconclusive (RR 1.00, 95% CI 0.91 to 1.09; 3 RCTs, N = 410; GRADE moderate quality).No conclusions possibleNo conclusions were possible for: lifestyle versus usual care (perineal trauma, postnatal depression, neonatal adiposity, number of antenatal visits/admissions); diet versus control (pre-eclampsia, caesarean section); myo-inositol versus placebo (hypoglycaemia); metformin versus glibenclamide (hypertensive disorders of pregnancy, pregnancy-induced hypertension, death or serious morbidity composite, insulin versus oral therapy (development of type 2 diabetes); intensive management versus routine care (IOL, large-for-gestational age); post- versus pre-prandial glucose monitoring (large-for-gestational age). The evidence ranged from moderate-, low- and very low-quality. Currently there is insufficient high-quality evidence about the effects on health outcomes of relevance for women with GDM and their babies for many of the comparisons in this overview comparing treatment interventions for women with GDM. Lifestyle changes (including as a minimum healthy eating, physical activity and self-monitoring of blood sugar levels) was the only intervention that showed possible health improvements for women and their babies. Lifestyle interventions may result in fewer babies being large. Conversely, in terms of harms, lifestyle interventions may also increase the number of inductions. Taking insulin was also associated with an increase in hypertensive disorders, when compared to oral therapy. There was very limited information on long-term health and health services costs. Further high-quality research is needed.

Effect of partograph use on outcomes for women in spontaneous labour at term and their babies.

Effect of partograph use on outcomes for women in spontaneous labour at term and their babies.

Metformin for women who are overweight or obese during pregnancy for improving maternal and infant outcomes.

Metformin for women who are overweight or obese during pregnancy for improving maternal and infant outcomes.

Vaginal preparation with antiseptic solution before cesarean section for preventing postoperative infections.

Cesarean delivery is one of the most common surgical procedures performed by obstetricians. Infectious morbidity after cesarean delivery can have a tremendous impact on the postpartum woman's return to normal function and her ability to care for her baby. Despite the widespread use of prophylactic antibiotics, postoperative infectious morbidity still complicates cesarean deliveries. This is an update of a Cochrane review first published in 2010 and subsequently updated in 2012, and twice in 2014. To determine if cleansing the vagina with an antiseptic solution before a cesarean delivery decreases the risk of maternal infectious morbidities, including endometritis and wound complications. We also assessed the side effects of vaginal cleansing solutions to determine adverse events associated with the intervention. We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (10 July 2017), and reference lists of retrieved studies. We included randomized trials and one quasi-randomized trial assessing the impact of vaginal cleansing immediately before cesarean delivery with any type of antiseptic solution versus a placebo solution/standard of care on post-cesarean infectious morbidity. Cluster-randomized trials were eligible for inclusion but none were identified. We excluded trials that utilized vaginal preparation during labor or that did not use antibiotic surgical prophylaxis. We also excluded any trials using a cross-over design. At least three of the review authors independently assessed eligibility of the studies. Two review authors were assigned to extract study characteristics, quality assessments, and data from eligible studies. We included 11 trials reporting results for 3403 women evaluating the effects of vaginal cleansing (eight using povidone-iodine, two chlorhexidine, one benzalkonium chloride) on post-cesarean infectious morbidity. Additionally, some trials used vaginal preparations using sponge sticks, douches, or soaked gauze wipes. The control groups were typically no vaginal preparation (eight trials) or the use of a saline vaginal preparation (three trials). The risk of bias in the studies reduced our confidence in the results for endometritis outcomes.Vaginal preparation with antiseptic solution immediately before cesarean delivery probably reduces the incidence of post-cesarean endometritis from 8.7% in control groups to 3.8% in vaginal cleansing groups (average risk ratio (RR) 0.36, 95% confidence interval (CI) 0.20 to 0.63, 10 trials, 3283 women, moderate quality of evidence). Subgroup analysis could not rule out larger reductions in endometritis with antiseptics in women who were in labor or in women whose membranes had ruptured when antiseptics were used. Risks of postoperative fever and postoperative wound infection may be slightly lowered by antiseptic preparation, but the confidence intervals around the effects for both outcomes are consistent with a large reduction in risk and no difference between groups (fever: RR 0.87 (0.72 to 1.05; wound infection: RR 0.74 (95% CI 0.49 to 1.11), both moderate-quality evidence). Two trials reported a lower risk of a composite outcome of wound complication or endometritis in women receiving preoperative vaginal preparation (RR 0.46, 95% CI 0.26 to 0.82, two trials, 499 women, moderate-quality evidence). No adverse effects were reported with either the povidone-iodine or chlorhexidine vaginal cleansing. Vaginal preparation with povidone-iodine or chlorhexidine solution compared to saline or not cleansing immediately before cesarean delivery probably reduces the risk of post-cesarean endometritis. Subgroup analysis could not rule out larger reductions in endometritis with antiseptics in women who were in labor or in women whose membranes had ruptured when antiseptics were used.The quality of the evidence using GRADE was moderate for all reported outcomes. We downgraded the outcome of post-cesarean endometritis and composite of wound complications or endometritis for risk of bias and postoperative fever and postoperative wound infections for wide CIs.As a simple, generally inexpensive intervention, providers may consider implementing preoperative vaginal cleansing with povidone-iodine or chlorhexidine before performing cesarean deliveries.

Prophylactic use of ergot alkaloids in the third stage of labour.

Previous research has shown that the prophylactic use of uterotonic agents in the third stage of labour reduces postpartum blood loss and moderate to severe postpartum haemorrhage (PPH). PPH is defined as a blood loss of 500 mL or more within 24 hours after birth. This is one of a series of systematic reviews assessing the effects of prophylactic use of uterotonic drugs; in this review prophylactic ergot alkaloids as a whole, and different regimens of administration of ergot alkaloids, are compared with no uterotonic agents. This is an update of a Cochrane Review which was first published in 2007 and last updated in 2011. To determine the effectiveness and safety of prophylactic use of ergot alkaloids in the third stage of labour by any route (intravenous (IV), intramuscular (IM), or oral) compared with no uterotonic agents, for the prevention of PPH. For this update, we searched the Cochrane Pregnancy and Childbirth Group's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (19 September 2017); we also searched reference lists of retrieved studies. We included all randomised controlled trials or cluster-randomised trials comparing prophylactic ergot alkaloids by any route (IV, IM, or oral) with no uterotonic agents in the third stage of labour among women giving birth vaginally. Two review authors independently assessed trials for inclusion, extracted data and checked them for accuracy; they also assessed the risk of bias in included studies. Two review authors assessed the quality of the evidence using the GRADE approach. There were eight included studies: three studies had a low risk of bias and five studies had high risk of bias. The studies compared ergot alkaloids with no uterotonic agents, with a total of 2031 women in the ergot alkaloids group and 1978 women in the placebo or no treatment group. Seven studies used the IV/IM route of administration and one study used the oral route.Ergot alkaloids (any route of administration) versus no uterotonic agentsUse of ergot alkaloids in the third stage of labour decreased mean blood loss (mean difference (MD) -80.52 mL, 95% confidence interval (CI) -96.39 to -64.65 mL; women = 2718; studies = 3; moderate-quality evidence); decreased PPH of at least 500 mL (average risk ratio (RR) 0.52, 95% CI 0.28 to 0.94; women = 3708; studies = 5; I2 = 83%; low-quality evidence); increased maternal haemoglobin concentration (g/dL) at 24 to 48 hours postpartum (MD 0.50 g/dL, 95% CI 0.38 to 0.62; women = 1429; studies = 1; moderate-quality evidence); and decreased the use of therapeutic uterotonics (average RR 0.37, 95% CI 0.15 to 0.90; women = 2698; studies = 3; I2 = 89%; low-quality evidence). There were no clear differences between groups in severe PPH of at least 1000 mL (average RR 0.32, 95% CI 0.04 to 2.59; women = 1718; studies = 2; I2 = 74%; very low-quality evidence). The risk of retained placenta or manual removal of the placenta, or both, were inconsistent with high heterogeneity. Ergot alkaloids increased the risk of elevated blood pressure (average RR 2.60, 95% CI 1.03 to 6.57: women = 2559; studies = 3; low-quality evidence) and pain after birth requiring analgesia (RR 2.53, 95% CI 1.34 to 4.78: women = 1429; studies = 1; moderate-quality evidence) but there were no differences between groups in vomiting, nausea, headache or eclamptic fit.Results for IV/IM ergot alkaloids versus no uterotonic agents were similar to those for the main comparison of ergot alkaloids administered by any route, since most of the studies (seven of eight) used the IV/IM route. Only one small study (289 women) compared oral ergometrine with placebo and it showed no benefit of ergometrine over placebo. No maternal adverse effects were reported.None of the studies reported on any of our prespecified neonatal outcomes AUTHORS' CONCLUSIONS: Prophylactic IM or IV injections of ergot alkaloids may be effective in reducing blood loss, reducing PPH (estimated blood loss of at least 500 mL), and increasing maternal haemoglobin. Ergot alkaloids may also decrease the use of therapeutic uterotonics, but adverse effects may include elevated blood pressure and pain after birth requiring analgesia. There were no differences between groups in terms of other adverse effects (vomiting, nausea, headache or eclamptic fit). There is a lack of evidence on the effects of ergot alkaloids on severe PPH, and retained or manual removal of placenta. There is also a lack of evidence on the oral route of administration of ergot alkaloids.

Epidural versus non-epidural or no analgesia for pain management in labour.

Epidural versus non-epidural or no analgesia for pain management in labour.

Immersion in water during labour and birth.

Background Enthusiasts suggest that labouring in water and waterbirth increase maternal relaxation, reduce analgesia requirements and promote a midwifery model of care. Critics cite the risk of neonatal water inhalation and maternal/neonatal infection. Objectives To assess the evidence from randomised controlled trials about immersion in water during labour and waterbirth on maternal, fetal, neonatal and caregiver outcomes. Search methods We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 June 2011) and reference lists of retrieved studies. Selection criteria Randomised controlled trials comparing immersion in any bath tub/pool with no immersion, or other non-pharmacological forms of pain management during labour and/or birth, in women during labour who were considered to be at low risk of complications, as defined by the researchers. Data collection and analysis We assessed trial eligibility and quality and extracted data independently. One review author entered data and the other checked for accuracy. Main results This review includes 12 trials (3243 women): eight related to just the first stage of labour: one to early versus late immersion in the first stage of labour; two to the first and second stages; and another to the second stage only. We identified no trials evaluating different baths/pools, or the management of third stage of labour. Results for the first stage of labour showed there was a significant reduction in the epidural/spinal/paracervical analgesia/anaesthesia rate amongst women allocated to water immersion compared to controls (478/1254 versus 529/1245; risk ratio (RR) 0.90; 95% confidence interval (CI) 0.82 to 0.99, six trials). There was also a reduction in duration of the first stage of labour (mean difference -32.4 minutes; 95% CI -58.7 to -6.13). There was no difference in assisted vaginal deliveries (RR 0.86; 95% CI 0.71 to 1.05, seven trials), caesarean sections (RR 1.21; 95% CI 0.87 to 1.68, eight trials), use of oxytocin infusion (RR 0.64; 95%CI 0.32 to 1.28,five trials), perineal trauma or maternal infection. There were no differences for Apgar score less than seven at five minutes (RR 1.58; 95% CI 0.63 to 3.93, five trials), neonatal unit admissions (RR 1.06; 95% CI 0.71 to 1.57, three trials), or neonatal infection rates (RR 2.00; 95% CI 0.50 to 7.94, five trials). Of the three trials that compared water immersion during the second stage with no immersion, one trial showed a significantly higher level of satisfaction with the birth experience (RR 0.24; 95% CI 0.07 to 0.80). A lack of data for some comparisons prevented robust conclusions. Further research is needed. Authors' conclusions Evidence suggests that water immersion during the first stage of labour reduces the use of epidural/spinal analgesia and duration of the first stage of labour. There is limited information for other outcomes related to water use during the first and second stages of labour, due to intervention and outcome variability. There is no evidence of increased adverse effects to the fetus/neonate or woman from labouring in water or waterbirth. However, the studies are very variable and considerable heterogeneity was detected for some outcomes. Further research is needed.

Relaxation techniques for pain management in labour.

Relaxation techniques for pain management in labour.

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

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

Combined diet and exercise interventions for preventing gestational diabetes mellitus.

Combined diet and exercise interventions for preventing gestational diabetes mellitus.

Insulin for the treatment of women with gestational diabetes.

Insulin for the treatment of women with gestational diabetes.