Intramuscular versus intravenous oxytocin to prevent postpartum haemorrhage at vaginal delivery: randomised controlled trial

Recognition on pharmacodynamic ingredients of natural products

Natural products (NPs) play an irreplaceable role in the intervention of various diseases and have been considered a critical source of drug development. Many new pharmacodynamic compounds with potential clinical applications have recently been derived from NPs. These compounds range from small molecules to polysaccharides, polypeptides, proteins, self-assembled nanoparticles, and extracellular vesicles. This review summarizes various active substances found in NPs. The investigation of active substances in NPs can potentiate new drug development and promote the in-depth comprehension of the mechanism of action of NPs that can be beneficial in the prevention and treatment of human diseases.

Third stage of labor: evidence-based practice for prevention of adverse maternal and neonatal outcomes

The third stage of labor is defined as the time period between delivery of the fetus through delivery of the placenta. During a normal third stage, uterine contractions lead to separation and expulsion of the placenta from the uterus. Postpartum hemorrhage is a relatively common complication of the third stage of labor. Strategies have been studied to mitigate the risk of postpartum hemorrhage, leading to the widespread implementation of active management of the third stage of labor. Initially, active management of the third stage of labor consisted of a bundle of interventions including administration of a uterotonic agent, early cord clamping, controlled cord traction, and external uterine massage. However, the effectiveness of these interventions as a bundle has been questioned, leading to abandonment of some components in recent years. Despite this, upon review of selected international guidelines, we found that the term "active management of the third stage of labor" was still used, but recommendations for and against individual interventions were variable and not necessarily supported by current evidence. In this review, we: (1) examine the physiology of the third stage of labor, (2) present evidence related to interventions that prevent postpartum hemorrhage and promote maternal and neonatal health, (3) review current global guidelines and recommendations for practice, and (4) propose future areas of investigation. The interventions in this review include pharmacologic agents to prevent postpartum hemorrhage, cord clamping, cord milking, cord traction, cord drainage, early skin-to-skin contact, and nipple stimulation. Treatment of complications of the third stage of labor is outside of the scope of this review. We conclude that current evidence supports the use of effective pharmacologic postpartum hemorrhage prophylaxis, delayed cord clamping, early skin-to-skin contact, and controlled cord traction at delivery when feasible. The most effective uterotonic regimens for preventing postpartum hemorrhage after vaginal delivery include oxytocin plus ergometrine; oxytocin plus misoprostol; or carbetocin. After cesarean delivery, carbetocin or oxytocin as a bolus are the most effective regimens. There is inconsistent evidence regarding the use of tranexamic acid in addition to a uterotonic compared with a uterotonic alone for postpartum hemorrhage prevention after all deliveries. Because of differences in patient comorbidities, costs, and availability of resources and staff, decisions to use specific prevention strategies are dependent on patient- and system-level factors. We recommend that the term "active management of the third stage of labor" as a combined intervention no longer be used. Instead, we recommend that "third stage care" be adopted, which promotes the implementation of evidence-based interventions that incorporate practices that are safe and beneficial for both the woman and neonate.

Interkingdom Hormonal Regulations between Plants and Animals Provide New Insight into Food Safety

Food safety has become an attractive topic among consumers. Raw material production for food is also a focus of social attention. As hormones are widely used in agriculture and human disease control, consumers' concerns about the safety of hormone agents have never disappeared. The present review focuses on the interkingdom regulations of exogenous animal hormones in plants and phytohormones in animals, including physiology and stress resistance. We summarize these interactions to give the public, researchers, and policymakers some guidance and suggestions. Accumulated evidence demonstrates comprehensive hormonal regulation across plants and animals. Animal hormones, interacting with phytohormones, help regulate plant development and enhance environmental resistance. Correspondingly, phytohormones may also cause damage to the reproductive and urinary systems of animals. Notably, the disease-resistant role of phytohormones is revealed against neurodegenerative diseases, cardiovascular disease, cancer, and diabetes. These resistances derive from the control for abnormal cell cycle, energy balance, and activity of enzymes. Further exploration of these cross-kingdom mechanisms would surely be of greater benefit to human health and agriculture development.

Side-effects of intravenously versus intramuscularly oxytocin for postpartum hemorrhage: a systematic review and meta-analysis of randomized controlled trials

Background: Oxytocin is the gold standard uterotonic agent for prevention of postpartum hemorrhage. However, there is no consensus with clear evidence about the side-effects of oxytocin administered intravenously or intramuscularly for management of the third stage of labor. We conducted a systematic review and meta-analysis of randomized controlled trials to evaluate the side-effects of intravenously or intramuscularly oxytocin for preventing postpartum hemorrhage in the third stage of labor. Methods: Six representative databases were searched from the inception to July 2023. Randomized controlled trials which explored the intravenously and intramuscularly oxytocin and provided at least one side-effect were included. Statistical analysis included random or fixed-effect meta-analyses using relative risk. Results: Nine studies included, involving 8,295 participants. Ten types of side-effects were reported. There was no statistical difference in hypotension (RR = 1.01, 95%CI = 0.88-1.15), anemia (0.98, 0.83-1.15), tachycardia (0.90, 0.69-1.17), shivering (0.90, 0.69-1.17), headache (0.86, 0.31-2.37), nausea (0.70, 0.20-2.42), vomiting (0.97, 0.26-3.58), uvular edema (0.82, 0.23-2.91), diarrhea (0.97, 0.26-3.58), and fever (0.97, 0.26-3.58) between intravenously or intramuscularly groups. Conclusion: There are no significant differences of side-effects between intravenously and intramuscularly administration of oxytocin for preventing postpartum hemorrhage in the third labor. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=407571.

Postpartum haemorrhage in high-resource settings: Variations in clinical management and future research directions based on a comparative study of national guidelines

OBJECTIVE

To compare guidelines from eight high-income countries on prevention and management of postpartum haemorrhage (PPH), with a particular focus on severe PPH.

DESIGN

Comparative study.

SETTING

High-resource countries.

POPULATION

Women with PPH.

METHODS

Systematic comparison of guidance on PPH from eight high-income countries.

MAIN OUTCOME MEASURES

Definition of PPH, prophylactic management, measurement of blood loss, initial PPH-management, second-line uterotonics, non-pharmacological management, resuscitation/transfusion management, organisation of care, quality/methodological rigour.

CONCLUSIONS

Our study highlights areas where strong evidence is lacking. There is need for a universal definition of (severe) PPH. Consensus is required on how and when to quantify blood loss to identify PPH promptly. Future research may focus on timing and sequence of second-line uterotonics and non-pharmacological interventions and how these impact maternal outcome. Until more data are available, different transfusion strategies will be applied. The use of clear transfusion-protocols are nonetheless recommended to reduce delays in initiation. There is a need for a collaborative effort to develop standardised, evidence-based PPH guidelines.

RESULTS

Definitions of (severe) PPH varied as to the applied cut-off of blood loss and incorporation of clinical parameters. Dose and mode of administration of prophylactic uterotonics and methods of blood loss measurement were heterogeneous. Recommendations on second-line uterotonics differed as to type and dose. Obstetric management diverged particularly regarding procedures for uterine atony. Recommendations on transfusion approaches varied with different thresholds for blood transfusion and supplementation of haemostatic agents. Quality of guidelines varied considerably.

Vaginal Birth at Term - Part 2. Guideline of the DGGG, OEGGG and SGGG (S3-Level, AWMF Registry No. 015/083, December 2020)

Purpose This guideline aims to summarize the current state of knowledge about vaginal birth at term. The guideline focuses on definitions of the physiological stages of labor as well as differentiating between various pathological developments and conditions. It also assesses the need for intervention and the options to avoid interventions. The second part of this guideline presents recommendations and statements on care during the dilation and expulsion stages as well as during the placental/postnatal stage. Methods The German recommendations largely reproduce the recommendations of the National Institute for Health and Care Excellence (NICE) CG190 guideline "Intrapartum care for healthy women and babies". Other international guidelines were also consulted in individual cases when compiling this guideline. In addition, a systematic search and analysis of the literature was carried out using PICO questions where necessary, and other systematic reviews and individual studies were taken into account. For easier comprehension, the assessment tools of the Scottish Intercollegiate Guidelines Network (SIGN) were used to evaluate the quality of additionally consulted studies. Otherwise, the GRADE system was used for the NICE guideline, and the evidence reports of the IQWiG were used to evaluate the quality of the evidence. Recommendations Recommendations and statements were formulated based on identified evidence and/or a structured consensus.

Obstetric and Maternal Outcomes After B-Lynch Compression Sutures: A Meta-Analysis

This review article aimed to determine the obstetric and maternal outcomes after B-Lynch compression sutures to control atonic postpartum hemorrhage (PPH). This meta-analysis was performed after registering the protocol in the PROSPERO database with the registration number CRD42022355358. Two independent reviewers systematically searched electronic databases and search engines (PubMed, Cochrane Library, and Google Scholar) to retrieve published articles from inception to July 2022. The obstetric and maternal outcomes after the B-Lynch compression suture were computed using the random-effects model in pooled proportion with a 95% confidence interval (CI). Meta-regression analysis and subgroup analysis were performed to explain any source of possible heterogeneity. Quality assessment of the included studies was done using Joanna Briggs Institute (JBI) tools which are critical appraisal tools for systematic reviews and meta-analyses. This meta-analysis included a total of 30 studies involving 1,270 subjects. The pooled proportion of B-Lynch suture alone was 91% (95% CI = 82-97%). The combined proportion of B-Lynch suture plus another compression suture was 1% (95% CI = 0-3%), and the pooled proportion of B-Lynch suture plus vessel ligation was 3% (95% CI = 1-6%). The pooled proportions of PPH controlled and hysterectomies were 94% (95% CI = 91-97%, I² = 65.3%) and 7% (95% CI = 4-10%, I² = 72.13%), respectively. Therefore, B-Lynch suture (either alone or in combination with other techniques) is a simple and effective measure to control atonic PPH.

The Effect of Oxytocin plus Carboprost Methylate in Preventing Postpartum Hemorrhage in High-Risk Pregnancy and Its Effect on Blood Pressure

Objective. This study aimed to explore and analyze the effectiveness of oxytocin plus carboprost methylate in preventing postpartum hemorrhage in high-risk pregnancies and its effect on blood pressure. A total of 60 women with high-risk pregnancies who gave birth in our hospital from January 2020 to May 2021 were recruited and assigned via random number table method (1 : 1) to receive either oxytocin (control group) or oxytocin plus carboprost methylate (observation group). Outcome measures included hemorrhage and blood pressure. The bleeding volume of the women in the observation group (210.55 ± 45.98, 45.21 ± 9.27, and 73.74 ± 12.18) was significantly less than that in the control group during delivery and 2h and 24h after the delivery (276.91 ± 49.21, 72.98 ± 19.68, and 92.61 ± 15.67) (all P < 0.05). The observation group showed a significantly lower bleeding rate (6.67%) than the control group (16.67%) (P < 0.05). The two groups showed similar diastolic and systolic blood pressures (P > 0.05). Oxytocin plus carboprost methylate suppository effectively prevents postpartum hemorrhage in high-risk pregnancies, significantly reduces the amount of postpartum hemorrhage in high-risk pregnancies, and has little effect on the blood pressure of patients. Given its favorable treatment efficiency and high safety profile, this treatment protocol shows great potential for clinical application.

Placenta Previa Complicated with Endometriosis: Contemporary Clinical Management, Molecular Mechanisms, and Future Research Opportunities

Endometriosis is a common gynecological disease characterized by chronic inflammation, with an estimated prevalence of approximately 5–15% in reproductive-aged women. This study aimed to assess the relationship between placenta previa (PP) and endometriosis. We performed a systematic review of the literature until 30 June 2021, and 24 studies met the inclusion criteria. Using an adjusted pooled analysis, we found that women with endometriosis had a significantly increased rate of PP (adjusted odds ratio (OR) 3.17, 95% confidence interval (CI) 2.58–3.89) compared to those without endometriosis. In an unadjusted analysis, severe endometriosis was associated with an increased prevalence of PP (OR 11.86, 95% CI 4.32–32.57), whereas non-severe endometriosis was not (OR 2.16, 95% CI 0.95–4.89). Notably, one study showed that PP with endometriosis was associated with increased intraoperative bleeding (1.515 mL versus 870 mL, p < 0.01) compared to those without endometriosis. Unfortunately, no studies assessed the molecular mechanisms underlying PP in patients with endometriosis. Our findings suggest that there is a strong association between endometriosis and a higher incidence of PP, as well as poor surgical outcomes during cesarean delivery. Therefore, the development of novel therapeutic agents or methods is warranted to prevent PP in women with endometriosis.

Number and quality of randomized controlled trials in obstetrics published in the top general medical and obstetrics and gynecology journals

BACKGROUND

There has been an increasing number of randomized controlled trials published in obstetrics and maternal-fetal medicine to reduce biases of treatment effect and to provide insights on the cause-effect of the relationship between treatment and outcomes.

OBJECTIVE

This study aimed to identify obstetrical randomized controlled trials published in top weekly general medical journals and monthly obstetrics and gynecology journals, to assess their quality in reporting and identify factors associated with publication in different journals.

STUDY DESIGN

The 4 weekly medical journals with the highest 2019 impact factor (New England Journal of Medicine, The Lancet, The Journal of the American Medical Association, and British Medical Journal), the top 4 monthly obstetrics and gynecology journals with obstetrics-related research (American Journal of Obstetrics & Gynecology, Ultrasound in Obstetrics & Gynecology, Obstetrics & Gynecology, and the British Journal of Obstetrics and Gynaecology), and the American Journal of Obstetrics & Gynecology Maternal-Fetal Medicine were searched for obstetrical randomized controlled trials in the years 2018 to 2020. The primary outcome was the number of obstetrical randomized controlled trials published in the obstetrics and gynecology journals vs the weekly medical journals and the percentage of trials published, overall and per journal. The secondary outcomes included the proportion of positive vs negative trials overall and per journal and the assessment of the study characteristics of published trials, including quality assessment criteria.

RESULTS

Of the 4024 original research articles published in the 9 journals during the 3-year study period, 1221 (30.3%) were randomized controlled trials, with 137 (11.2%) randomized controlled trials being in obstetrics (46 in 2018, 47 in 2019, and 44 studies in 2020). Furthermore, 33 (24.1%) were published in weekly medical journals, and 104 (75.9%) were published in obstetrics and gynecology journals. The percentage of obstetrical randomized controlled trials published ranged from 1.5% to 9.6% per journal. Overall, 34.3% of obstetrical trials were statistically significant or "positive" for the primary outcome. Notably, 24.8% of the trials were retrospectively registered after the enrollment of the first study patient. Trials published in the 4 weekly medical journals enrolled significantly more patients (1801 vs 180; P<.001), received more often funding from the federal government (78.8% vs 35.6%; P<.001), and were more likely to be multicenter (90.9% vs 42.3%; P<.001), non-United States based (69.7% vs 49.0%; P=.03), and double blinded (45.5% vs 18.3%; P=.003) than trials published in the obstetrics and gynecology journals. There was no difference in study type (noninferiority vs superiority) and trial quality characteristics, including pretrial registration, ethics approval statement, informed consent statement, and adherence to the Consolidated Standards of Reporting Trials guidelines statement between studies published in weekly medical journals and studies published in obstetrics and gynecology journals.

CONCLUSION

Approximately 45 trials in obstetrics are being published every year in the highest impact journals, with one-fourth being in the weekly medical journals and the remainder in the obstetrics and gynecology journals. Only about a third of published obstetrical trials are positive. Trials published in weekly medical journals are larger, more likely to be funded by the government, multicenter, international, and double blinded. Quality metrics are similar between weekly medical journals and obstetrics and gynecology journals.

A systematic review and meta-analysis of obstetric and maternal outcomes after prior uterine artery embolization

This study aimed to review the obstetric complications during subsequent pregnancies after uterine artery embolization (UAE) for postpartum hemorrhage (PPH) by exploring the relationship between prior UAE and obstetric complications through a meta-analysis. We conducted a systematic literature review through March 31, 2021, using PubMed, Scopus, and the Cochrane Central Register of Controlled Trials in compliance with the PRISMA guidelines and determined the effect of prior UAE for PPH on the rate of placenta accreta spectrum (PAS), PPH, placenta previa, hysterectomy, fetal growth restriction (FGR), and preterm birth (PTB). Twenty-three retrospective studies (2003–2021) met the inclusion criteria. They included 483 pregnancies with prior UAE and 320,703 pregnancies without prior UAE. The cumulative results of all women with prior UAE indicated that the rates of obstetric complications PAS, hysterectomy, and PPH were 16.3% (34/208), 6.5% (28/432), and 24.0% (115/480), respectively. According to the patient background-matched analysis based on the presence of prior PPH, women with prior UAE were associated with higher rates of PAS (odds ratio [OR] 20.82; 95% confidence interval [CI] 3.27–132.41) and PPH (OR 5.32, 95% CI 1.40–20.16) but not with higher rates of hysterectomy (OR 8.93, 95% CI 0.43–187.06), placenta previa (OR 2.31, 95% CI 0.35–15.22), FGR (OR 7.22, 95% CI 0.28–188.69), or PTB (OR 3.00, 95% CI 0.74–12.14), compared with those who did not undergo prior UAE. Prior UAE for PPH may be a significant risk factor for PAS and PPH during subsequent pregnancies. Therefore, at the time of delivery, clinicians should be more attentive to PAS and PPH when women have undergone prior UAE. Since the number of women included in the patient background-matched study was limited, further investigations are warranted to confirm the results of this study.

Oxytocin Receptor Activation Rescues Opioid-Induced Respiratory Depression by Systemic Fentanyl in the Rat

Opioid overdose intervention by naloxone, a high affinity receptor antagonist, reverses opioid-induced respiratory depression (OIRD) and analgesia by displacing opioids. Systemic naloxone stimulates release of the hypothalamic neuropeptide oxytocin, which has analgesic properties and participates in cardiorespiratory homeostasis. To test the hypothesis that oxytocin can reverse OIRD, we assessed the rescue potential of graded doses (0, 0.1, 2, 5, 10, 50 nmol/kg, i.v.) of oxytocin to counter fentanyl (60 nmol/kg, i.v.)-induced depression of neural inspiration indexed by recording phrenic nerve activity (PNA) in anesthetized (urethane/α-chloralose), vagotomized, and artificially ventilated rats. Oxytocin dose-dependently rescued fentanyl OIRD by almost immediately reversing PNA burst arrest (P = 0.0057) and restoring baseline burst frequency (P = 0.0016) and amplitude (P = 0.0025) at low but not high doses, resulting in inverted bell-shaped dose-response curves. Oxytocin receptor antagonism (40 nmol/kg, i.v.) prevented oxytocin reversal of OIRD (arrest: P = 0.0066, frequency: P = 0.0207, amplitude: P = 0.0022). Vasopressin 1A receptor (V1aR) antagonism restored high-dose oxytocin efficacy to rescue OIRD (P = 0.0170 to P < 0.0001), resulting in classic sigmoidal dose-response curves, and prevented (P = 0.0135) transient hypertension from V1aR cross-activation (P = 0.0275). Alone, vasopressin (5 nmol/kg, i.v.) failed to reverse fentanyl respiratory arrest (P = 0.6184). The nonpeptide oxytocin receptor agonist WAY-267464 (75 nmol/kg, i.v.), which has V1aR antagonist properties, quickly reversed fentanyl OIRD (P < 0.0001), with rapid recovery of PNA frequency (P = 0.0011) and amplitude (P = 0.0044) without adverse hemodynamic consequences (P = 0.9991). Findings indicate that peptide and nonpeptide agonist activation of oxytocin receptors without V1aR cross-activation rescues fentanyl OIRD. Oxytocin receptor agonists could be lifesaving resuscitation agents that enhance rather than interrupt opioid analgesia. SIGNIFICANCE STATEMENT: Oxytocin receptor activation produces analgesia. Here, we demonstrate that activation by the US Food and Drug Administration-approved agonist oxytocin and the nonpeptide partial agonist WAY-267464 can each reverse fentanyl cardiorespiratory depression. Selective targeting of oxytocin receptors for resuscitation from opioid overdose, alone or in combination with an opioid antagonist, could eliminate or attenuate negative side effects associated with traditional opioid receptor antagonism.

Circular suture of the uterine serosa and myometrium layer around placental attachment site for refractory postpartum hemorrhage

OBJECTIVE

The aim of the study was to analyze the clinical outcomes of circular suture at placental attachment site for refractory postpartum hemorrhage (PPH), which could block blood supply of the serosa and myometrium layer.

METHODS

Eighty cases of refractory PPH were enrolled and retrospective analyzed in this study for further analysis from a consecutive single center database between 2010 and 2018. After undergoing circular suture of the uterine serosa and myometrium layer around placental attachment site, surgical and perioperative outcomes were recorded and analyzed.

RESULTS

Among all the patients enrolled, 28 cases (35.0%) of refractory PPH were mainly caused by uterine inertia, 36 cases (45.0%) caused by ectopic placenta, and 2 cases (2.5%) caused by coagulation disorders. After circular suture of the uterine serosa and myometrium layer at placental attachment site, all the uterine active bleeding was controlled below 40 ml without recurrence. The perioperative results were similar between the vaginal and cesarean sections groups.

CONCLUSIONS

Circular suture of the uterine serosa and myometrium at the placental attachment site could control refractory PPH with few postoperative complications. Circular suture around placenta site could be applied in time to protect the endometrium even in primary hospital.

Intramuscular oxytocin versus Syntometrine® versus carbetocin for prevention of primary postpartum haemorrhage after vaginal birth: a randomised double-blinded clinical trial of effectiveness, side effects and quality of life

OBJECTIVE

To compare intramuscular oxytocin, Syntometrine^® and carbetocin for prevention of postpartum haemorrhage after vaginal birth.

DESIGN

Randomised double-blinded clinical trial.

SETTING

Six hospitals in England.

POPULATION

A total of 5929 normotensive women having a singleton vaginal birth.

METHODS

Randomisation when birth was imminent.

MAIN OUTCOME MEASURES

Primary: use of additional uterotonic agents. Secondary: weighed blood loss, transfusion, manual removal of placenta, adverse effects, quality of life.

RESULTS

Participants receiving additional uterotonics: 368 (19.5%) oxytocin, 298 (15.6%) Syntometrine and 364 (19.1%) carbetocin. When pairwise comparisons were made: women receiving carbetocin were significantly more likely to receive additional uterotonics than those receiving Syntometrine (odds ratio [OR] 1.28, 95% CI 1.08-1.51, P = 0.004); the difference between carbetocin and oxytocin was non-significant (P = 0.78); Participants receiving Syntometrine were significantly less likely to receive additional uterotonics than those receiving oxytocin (OR 0.75, 95% CI 0.65-0.91, P = 0.002). Non-inferiority between carbetocin and Syntometrine was not shown. Use of Syntometrine reduced non-drug PPH treatments compared with oxytocin (OR 0.64, 95% CI 0.42-0.97) but not carbetocin (P = 0.64). Rates of PPH and blood transfusion were not different. Syntometrine was associated with an increase in maternal adverse effects and reduced ability of the mother to bond with her baby.

CONCLUSIONS

Non-inferiority of carbetocin to Syntometrine was not shown. Carbetocin is not significantly different to oxytocin for use of additional uterotonics. Use of Syntometrine reduced use of additional uterotonics and need for non-drug PPH treatments compared with oxytocin. Increased maternal adverse effects are a disadvantage of Syntometrine.

TWEETABLE ABSTRACT

IM carbetocin does not reduce additional uterotonic use compared with IM Syntometrine or oxytocin.

Intravenous versus intramuscular prophylactic oxytocin for the third stage of labour

BACKGROUND

There is general agreement that oxytocin given either through the intravenous or intramuscular route is effective in reducing postpartum blood loss. However, it is unclear whether the subtle differences between the mode of action of these routes have any effect on maternal and infant outcomes. This review was first published in 2012 and last updated in 2018.

OBJECTIVES

To determine the comparative effectiveness and safety of oxytocin administered intravenously or intramuscularly for prophylactic management of the third stage of labour after vaginal birth.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (19 December 2019), and reference lists of retrieved studies.

SELECTION CRITERIA

Eligible studies were randomised trials comparing intravenous with intramuscular oxytocin for prophylactic management of the third stage of labour after vaginal birth. We excluded quasi-randomised trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion and risk of bias, extracted data and checked them for accuracy. We assessed the certainty of the evidence with the GRADE approach.

MAIN RESULTS

Seven trials, involving 7817 women, met the inclusion criteria for this review. The trials compared intravenous versus intramuscular administration of oxytocin just after the birth of the anterior shoulder or soon after the birth of the baby. All trials were conducted in hospital settings and included women with term pregnancies, undergoing a vaginal birth. Overall, the included studies were at moderate or low risk of bias, with two trials providing clear information on allocation concealment and blinding. For GRADE outcomes, the certainty of the evidence was generally moderate to high, except from two cases where the certainty of the evidence was either low or very low. High-certainty evidence suggests that intravenous administration of oxytocin in the third stage of labour compared with intramuscular administration carries a lower risk for postpartum haemorrhage (PPH) ≥ 500 mL (average risk ratio (RR) 0.78, 95% confidence interval (CI) 0.66 to 0.92; six trials; 7731 women) and blood transfusion (average RR 0.44, 95% CI 0.26 to 0.77; four trials; 6684 women). Intravenous administration of oxytocin probably reduces the risk of PPH ≥ 1000 mL, although the 95% CI crosses the line of no-effect (average RR 0.65, 95% CI 0.39 to 1.08; four trials; 6681 women; moderate-certainty evidence). In all studies but one, there was a reduction in the risk of PPH ≥ 1000 mL with intravenous oxytocin. The study that found a large increase with intravenous administration was small (256 women), and contributed only 3% of total events. Once this small study was removed from the meta-analysis, heterogeneity was eliminated and the treatment effect favoured intravenous oxytocin (average RR 0.61, 95% CI 0.42 to 0.88; three trials; 6425 women; high-certainty evidence). Additionally, a sensitivity analysis, exploring the effect of risk of bias by restricting analysis to those studies rated as 'low risk of bias' for random sequence generation and allocation concealment, found that the prophylactic administration of intravenous oxytocin reduces the risk for PPH ≥ 1000 mL, compared with intramuscular oxytocin (average RR 0.64, 95% CI 0.43 to 0.94; two trials; 1512 women). The two routes of oxytocin administration may be comparable in terms of additional uterotonic use (average RR 0.78, 95% CI 0.49 to 1.25; six trials; 7327 women; low-certainty evidence). Although intravenous compared with intramuscular administration of oxytocin probably results in a lower risk for serious maternal morbidity (e.g. hysterectomy, organ failure, coma, intensive care unit admissions), the confidence interval suggests a substantial reduction, but also touches the line of no-effect. This suggests that there may be no reduction in serious maternal morbidity (average RR 0.47, 95% CI 0.22 to 1.00; four trials; 7028 women; moderate-certainty evidence). Most events occurred in one study from Ireland reporting high dependency unit admissions, whereas in the remaining three studies there was only one case of uvular oedema. There were no maternal deaths reported in any of the included studies (very low-certainty evidence). There is probably little or no difference in the risk of hypotension between intravenous and intramuscular administration of oxytocin (RR 1.01, 95% CI 0.88 to 1.15; four trials; 6468 women; moderate-certainty evidence). Subgroup analyses based on the mode of administration of intravenous oxytocin (bolus injection or infusion) versus intramuscular oxytocin did not show any substantial differences on the primary outcomes. Similarly, additional subgroup analyses based on whether oxytocin was used alone or as part of active management of the third stage of labour (AMTSL) did not show any substantial differences between the two routes of administration.

AUTHORS' CONCLUSIONS

Intravenous administration of oxytocin is more effective than its intramuscular administration in preventing PPH during vaginal birth. Intravenous oxytocin administration presents no additional safety concerns and has a comparable side effects profile with its intramuscular administration. Future studies should consider the acceptability, feasibility and resource use for the intervention, especially in low-resource settings.

The association of shock index and haemoglobin variation with postpartum haemorrhage after vaginal delivery: a prospective cohort pilot study

INTRODUCTION

Shock index and continuous non-invasive haemoglobin monitoring (SpHb) have both been proposed for the timely recognition of postpartum haemorrhage (PPH). We sought to determine, in parallel, the association of each of shock index and SpHb with blood loss after vaginal delivery.

METHODS

Sixty-six women were recruited to this prospective observational study. Shock index and SpHb were recorded postpartum for 120 min. The association between each of shock index and SpHb with quantitative blood loss (QBL) at 30, 60 and 120 min postpartum was determined using linear mixed models. Area-under-the-receiver-operator-characteristic (AUROC) curves were constructed to evaluate the diagnostic ability of shock index and SpHb to detect PPH (defined as QBL ≥1000 mL).

RESULTS

Shock index trend was associated with QBL over the first 30 min (r=0.37, P=0.002), but not over 60 or 120 min. There was an association of SpHb trend with QBL over the first 30 min (P=0.06), but not over 60 min (r=-0.32, P=0.009) or 120 min (r=-0.26, P=0.03). Maximum shock index within 60 min correlated with QBL (r=0.54, P <0.001) and was a predictor of PPH (P=0.0012, AUROC 0.796). Maximum change in SpHb within 60 min negatively correlated with QBL (r=-0.4, P <0.001) and was a predictor of PPH (P=0.048, AUROC 0.761).

CONCLUSIONS

The trend of shock index and its peak values are associated with blood loss after vaginal delivery and are early indicators of PPH. Negative trend of SpHb is a late sign of PPH and has a weaker association with blood loss than shock index.

The PRECIS-2 tool seems not to be useful to discriminate the degree of pragmatism of medicine masked trials from that of open-label trials

PURPOSE

To assess, with all available trial information, whether the assessment of the PRECIS-2 nine domains could provide a clear distinction between medicine masked pragmatic randomized controlled trials (pRCTs) and open-label pRCTs.

METHODS

A search was conducted of participant-level pRCTs on medicines published on 25 influential medical journals in July 2018-December 2019. All pre-licensing (phases 1-3) and cluster pRCTs were excluded. All trials' available reports were searched through the published article information, Google Scholar, and trial websites. Instead of providing a score to each PRECIS-2 domain, these were classified as E (explanatory), N (neutral), or P (pragmatic).

RESULTS

Of 128 pRCTs, 18 (14%) were participant-level pRCTs on medicines. The full trial protocol was available for 14 trials; 12 had published the protocol and nine had additional reports published. All trials were prospectively registered, and none was funded by industry. Ten and eight were masked and open-label trials, respectively. Masked pRCTS had 34% of pragmatic and 60% of explanatory domains; open-label pRCTS had 45% pragmatic and 45% explanatory domains. Among the 10 masked trials, only one had a majority of five pragmatic domains; among the eight open-label trials, four had a majority of six or five pragmatic domains. "Follow-up" was considered explanatory in the 18 pRCTs; "primary analysis" was pragmatic in 17 pRCTs.

CONCLUSION

The PRECIS-2 tool seems not to be sensitive enough to clearly discriminate between medicine masked pRCTs and open-label pRCTs. When conducting systematic reviews, it is suggested that the PRECIS-2 tool should not be used to support placing masked trials in the pragmatic side of the explanatory/pragmatic continuum.

Gerard W. Ostheimer Lecture: What's New in Obstetric Anesthesia 2018

This article summarizes the Gerard W. Ostheimer Lecture given at the 2019 Society for Obstetric Anesthesia and Perinatology annual meeting. The article summarizes key articles published in 2018 that were presented in the 2019 Ostheimer Lecture, with a focus on maternal mortality, maternal complications, analgesic and anesthetic management of vaginal and cesarean deliveries, postpartum care, and the impact of anesthesia on maternal outcomes. The reviewed literature highlights many opportunities for anesthesiologists to impact maternal care and outcomes. The major themes presented in this manuscript are maternal mortality including amniotic fluid and cardiac arrest; postpartum hemorrhage; venous thromboembolism; management of spinal-induced hypotension; postpartum care including opioid use, postcesarean analgesia, and postpartum depression. A proposed list of action items and research topics based on the literature from 2018 is also presented. Specifically, anesthesiologists should use prophylactic vasopressor infusions during elective cesarean delivery; use a structured algorithm to diagnose pulmonary embolus, and reevaluate the use of D-dimer measurements; target postpartum opioid analgesia and prescribing; use multimodal postcesarean delivery analgesia, preferably with neuraxial hydrophilic opioids; and study any association between labor analgesia on postpartum depression.

Intravenous Oxytocin versus Intramuscular Oxytocin for the Management of Postpartum Hemorrhage: A Systematic Review and Meta-Analysis

BACKGROUND

Postpartum Hemorrhage (PPH) is one of the primary causes of maternal mortality and morbidity during the third stage of labor. Oxytocin is the gold standard uterotonic agent for the prevention of PPH.

OBJECTIVE

We aimed to compare the efficacy of oxytocin administered Intramuscularly (IM) or Intravenously (IV) for the preventive management of PPH.

METHODS

We searched six databases for relevant clinical trials evaluating the administration of oxytocin for the prevention against PPH through July 2019. Data on blood loss, PPH (≥500 ml), severe PPH (≥1000 ml), blood transfusion, the change in hemoglobin, the use of additional uterotonics, and the incidence of retained placenta were extracted and pooled in a meta-analysis model using RevMan version 5.3.

RESULTS

Seven studies with a total of 6996 participants were included. IM oxytocin group was associated with higher incidence rates of PPH (≥500 ml) (RR=1.35; p=0.003), severe PPH (≥1000 ml) (RR=1.58; p=0.04), and blood transfusion (RR=2.43; p=0.005). In terms of blood loss, the IV route was superior to the IM route (SMD= 0.15; p=0.00001). However, we observed no statistically significant difference between the two routes regarding the change in Hb (SMD=-0.02; p=0.72) and the use of additional uterotonics (RR=0.96, p= 0.94).

CONCLUSION

IV oxytocin infusion is maybe superior to IM injection for the management of PPH. Further studies with larger sample sizes are still needed to support these findings.

Articles provided insufficient information to conduct an appropriate retrospective assessment of the pragmatic/explanatory features of medicine trials with the PRECIS-2 tool

PURPOSE

To assess whether, in the retrospective assessment of the pragmatic/explanatory features of pragmatic randomized controlled trials (pRCTs), the nine PRECIS-2 domain scores using the information provided in articles were modified after using the information reported in other publicly available sources.

METHODS

This is a cross-sectional study of participant-level pRCTs published in July 2018 to December 2019 in the four highest-impact general medicine journals. The articles described the main results of pRCTs assessing medicines in one or more arms that were not in the pre-licensing phases. The information reported in trial full protocols, published protocols, and other publications, registries, and trial websites were assessed and scored, and compared with that previously obtained after reviewing the information reported in the articles.

RESULTS

Out of 76 articles on pRCTs, 13 (17%) were included in the analysis. All were two-arm trials, assessing medicines only (n = 7), medicine vs device (n = 2), medicine vs surgery (n = 1), or medicine vs placebo (n = 3). Seven were open-label trials, and six had any type of masking. All except one had the full protocol available and/or published protocol; seven had other types of publication available. The assessment of the nine PRECIS-2 domains with the information reported in the 13 articles was changed in all trials after using the information included in other additional available sources. Between one (n = 1 article) and six (n = 2) domains were modified in each pRCT. The domains that most commonly changed were "organization" (n = 12), "recruitment" (n = 11), and "follow-up" (n = 8). "Primary outcome" and "primary analysis" were not modified in any trial. Eight percent of all domains could not be assessed due to inadequate or lack of information in seven articles; those were "recruitment" (n = 3), "organization" (n = 3), "setting" (n = 2), and "flexibility:adherence" (n = 1).

CONCLUSION

Articles describing the trial main results are usually insufficient for the appropriate retrospective assessment of the pragmatic/explanatory features of a pRCT by authors not involved in the conduct of the trial. To address this issue, editors should require the submission of the original full protocol and final full protocol with the history of amendments to be published as supplementary material to the article.

Incidence of postpartum haemorrhage defined by quantitative blood loss measurement: a national cohort

BACKGROUND

Visual estimation of blood loss following delivery often under-reports actual bleed volume. To improve accuracy, quantitative blood loss measurement was introduced for all births in the 12 hospitals providing maternity care in Wales. This intervention was incorporated into a quality improvement programme (Obstetric Bleeding Strategy for Wales, OBS Cymru). We report the incidence of postpartum haemorrhage in Wales over a 1-year period using quantitative measurement.

METHODS

This prospective, consecutive cohort included all 31,341 women giving birth in Wales in 2017. Standardised training was cascaded to maternity staff in all 12 hospitals in Wales. The training comprised mock-scenarios, a video and team drills. Uptake of quantitative blood loss measurement was audited at each centre. Data on postpartum haemorrhage of > 1000 mL were collected and analysed according to mode of delivery. Data on blood loss for all maternities was from the NHS Wales Informatics Service.

RESULTS

Biannual audit data demonstrated an increase in quantitative measurement from 52.1 to 87.8% (P < 0.001). The incidence (95% confidence intervals, CI) of postpartum haemorrhage of > 1000 mL, > 1500 mL and > 2000 mL was 8.6% (8.3 to 8.9), 3.3% (3.1 to 3.5) and 1.3% (1.2 to 1.4), respectively compared to 5%, 2% and 0.8% in the year before OBS Cymru. The incidence (95% CI) of bleeds of > 1000 mL was similar across the 12 hospitals despite widely varied size, staffing levels and case mix, median (25th to 75th centile) 8.6% (7.8-9.6). The incidence of PPH varied with mode of delivery and was mean (95% CI) 4.9% (4.6-5.2) for unassisted vaginal deliveries, 18.4 (17.1-19.8) for instrumental vaginal deliveries, 8.5 (7.7-9.4) for elective caesarean section and 19.8 (18.6-21.0) for non-elective caesarean sections.

CONCLUSIONS

Quantitative measurement of blood loss is feasible in all hospitals providing maternity care and is associated with detection of higher rates of postpartum haemorrhage. These results have implications for the definition of abnormal blood loss after childbirth and for management and research of postpartum haemorrhage.

Introduction of standardized, cumulative quantitative measurement of blood loss into routine maternity care

Introduction: Postpartum hemorrhage (PPH) is the leading cause of maternal morbidity in the UK. Visual estimation of blood loss is unreliable yet remains common practice. As part of a national quality improvement project to improve care during PPH, standardized, quantitative measurement of blood loss (QBL) for all deliveries was introduced into a tertiary obstetric unit in Cardiff, Wales.Methods: Retrospective analysis of 875 consecutive maternities between December 2017 and February 2018 was undertaken. Of these, 372 mothers had both pre- and post-partum hemoglobin (Hb) were recorded. Regression analyses were performed to investigate the relationship between change in Hb adjusted for red cell transfusion and QBL.Results: The correlation coefficient between QBL and adjusted change in Hb for all deliveries (n = 372) was 0.57. This corresponded to an estimated fall of adjusted change in Hb of 15.3 g/L (95% CI: 13.1, 17.6) per 1000 mL blood loss.Discussion: QBL has been shown to be reliable across all maternity settings, with reproducible results in theater and delivery rooms (on the obstetric unit and alongside midwifery-led unit). QBL is moderately correlated with adjusted change in Hb for all volumes of bleeding and gives clinicians more accurate knowledge of blood loss than visual estimation. This low-cost, low-fidelity intervention can influence the timely escalation of clinical care and therefore patient outcome.

Does route matter? Impact of route of oxytocin administration on postpartum bleeding: A double-blind, randomized controlled trial

OBJECTIVE

We assessed the impact of intravenous (IV) infusion versus intramuscular (IM) oxytocin on postpartum blood loss and rates of postpartum hemorrhage (PPH) when administered during the third stage of labor. While oxytocin is recommended for prevention of PPH, few double-blind studies have compared outcomes by routes of administration.

METHODS

A double-blind, placebo-controlled randomized trial was conducted at a hospital in Argentina. Participants were assigned to receive 10 IU oxytocin via IV infusion or IM injection and a matching saline ampoule for the other route after vaginal birth. Blood loss was measured using a calibrated receptacle for a 1-hour minimum. Shock index (SI) was also calculated, based on vital signs measurements, and additional interventions were recorded. Primary outcomes included: the frequency of blood loss ≥500ml and mean blood loss.

RESULTS

239 (IV infusion) and 241 (IM) women were enrolled with comparable baseline characteristics. Mean blood loss was 43ml less in the IV infusion group (p = 0.161). Rates of blood loss ≥500ml were similar (IV infusion = 21%; IM = 24%, p = 0.362). Women in the IV infusion group received significantly fewer additional uterotonics (5%), than women in the IM group (12%, p = 0.007). Women with PPH in the IM group experienced a larger increase in SI after delivery, which may have influenced recourse to additional interventions.

CONCLUSIONS

The route of oxytocin administration for PPH prevention did not significantly impact measured blood loss after vaginal birth. However, differences were observed in recourse to additional uterotonics, favoring IV infusion over IM. In settings where IV lines are routinely placed, oxytocin infusion may be preferable to IM injection.

A network pharmacology approach to investigate the blood enriching mechanism of Danggui buxue Decoction

ETHNOPHARMACOLOGICAL RELEVANCE

Danggui buxue Decoction (DBD) has been frequently used to treat with blood deficiency, which consisted of Danggui (DG) and Huangqi (HQ) at a ratio of 1:5. Accumulating evidence showed that blood deficiency in traditional Chinese medicine (TCM) was similar to anemia in modern medicine.

AIM OF THE STUDY

The purpose of this study was to explore its therapeutic mechanism of with network pharmacology approach.

MATERIALS AND METHODS

We explored the chemical compounds of DBD and used compound ADME screening to identify the potential compounds. Targets for the therapeutic actions of DBD were obtained from the PharmMapper, Swiss, SEA and STITCH. GO analysis and pathway enrichment analysis was performed using the DAVID webserver. Cytoscape was used to visualize the compound-target-pathway network for DBD. The pharmacodynamics and crucial targets were also validated.

RESULTS

Thirty-six potential active components in DBD and 49 targets which the active components acted on were identified. 47 KEGG pathways which DBD acted on were also come to light. And then, according to KEGG pathway annotation analysis, only 16 pathways seemed to be related to the blood nourishing effect of DBD, such as PI3K-AKT pathway, and so on. Only 32 targets participated in these 16 pathways and they were acted on by 29 of the 36 active compounds. Whole pharmacodynamic experiments showed that DBD had significant effects to blood loss rats. Furthermore, DBD could promote the up-regulation of hematopoietic and immune related targets and the down-regulation of inflammatory related targets. Significantly, with the results of effective rate, molecular docking and experimental validation, we predicted astragaloside IV in HQ, senkyunolide A and senkyunolide K in DG might be the major contributing compounds to DBD's blood enriching effect.

CONCLUSION

In this study, a systematical network pharmacology approach was built. Our results provided a basis for the future study of senkyunolide A and senkyunolide K as the blood enriching compounds in DBD. Furthermore, combined network pharmacology with validation experimental results, the nourishing blood effect of DBD might be manifested by the dual mechanism of enhancing immunity and promoting hematopoiesis.

Patient blood management in obstetrics: prevention and treatment of postpartum haemorrhage. A NATA consensus statement

Patient blood management (PBM) is the timely application of evidence-informed medical and surgical concepts designed to maintain haemoglobin concentration, optimise haemostasis, and minimise blood loss in an effort to improve patient outcomes. The aim of this consensus statement is to provide recommendations on the prevention and treatment of postpartum haemorrhage as part of PBM in obstetrics. A multidisciplinary panel of physicians with expertise in obstetrics, anaesthesia, haematology, and transfusion medicine was convened by the Network for the Advancement of Patient Blood Management, Haemostasis and Thrombosis (NATA) in collaboration with the International Federation of Gynaecology and Obstetrics (FIGO), the European Board and College of Obstetrics and Gynaecology (EBCOG), and the European Society of Anaesthesiology (ESA). Members of the task force assessed the quantity, quality and consistency of the published evidence, and formulated recommendations using the system developed by the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) working group. The recommendations in this consensus statement are intended for use by clinical practitioners managing perinatal care of women in all settings, and by policy-makers in charge of decision making for the update of clinical practice in health care establishments.

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

BACKGROUND

Active management of the third stage of labour involves giving a prophylactic uterotonic, early cord clamping and controlled cord traction to deliver the placenta. With expectant management, signs of placental separation are awaited and the placenta is delivered spontaneously. Active management was introduced to try to reduce haemorrhage, a major contributor to maternal mortality in low-income countries. This is an update of a review last published in 2015.

OBJECTIVES

To compare the effects of active versus expectant management of the third stage of labour on severe primary postpartum haemorrhage (PPH) and other maternal and infant outcomes.To compare the effects of variations in the packages of active and expectant management of the third stage of labour on severe primary PPH and other maternal and infant outcomes.

SEARCH METHODS

For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov and the World health Organization International Clinical Trials Registry Platform (ICTRP), on 22 January 2018, and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials comparing active versus expectant management of the third stage of labour. Cluster-randomised trials were eligible for inclusion, but none were identified.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the studies for inclusion, assessed risk of bias, carried out data extraction and assessed the quality of the evidence using the GRADE approach.

MAIN RESULTS

We included eight studies, involving analysis of data from 8892 women. The studies were all undertaken in hospitals, seven in higher-income countries and one in a lower-income country. Four studies compared active versus expectant management, and four compared active versus a mixture of managements. We used a random-effects model in the analyses because of clinical heterogeneity. Of the eight studies included, we considered three studies as having low risk of bias in the main aspects of sequence generation, allocation concealment and completeness of data collection. There was an absence of high-quality evidence according to GRADE assessments for our primary outcomes, which is reflected in the cautious language below.The evidence suggested that, for women at mixed levels of risk of bleeding, it is uncertain whether active management reduces the average risk of maternal severe primary PPH (more than 1000 mL) at time of birth (average risk ratio (RR) 0.34, 95% confidence interval (CI) 0.14 to 0.87, 3 studies, 4636 women, I2 = 60%; GRADE: very low quality). For incidence of maternal haemoglobin (Hb) less than 9 g/dL following birth, active management of the third stage may reduce the number of women with anaemia after birth (average RR 0.50, 95% CI 0.30 to 0.83, 2 studies, 1572 women; GRADE: low quality). We also found that active management of the third stage may make little or no difference to the number of babies admitted to neonatal units (average RR 0.81, 95% CI 0.60 to 1.11, 2 studies, 3207 infants; GRADE: low quality). It is uncertain whether active management of the third stage reduces the number of babies with jaundice requiring treatment (RR 0.96, 95% CI 0.55 to 1.68, 2 studies, 3142 infants, I2 = 66%; GRADE: very low quality). There were no data on our other primary outcomes of very severe PPH at the time of birth (more than 2500 mL), maternal mortality, or neonatal polycythaemia needing treatment.Active management reduces mean maternal blood loss at birth and probably reduces the rate of primary blood loss greater than 500 mL, and the use of therapeutic uterotonics. Active management also probably reduces the mean birthweight of the baby, reflecting the lower blood volume from interference with placental transfusion. In addition, it may reduce the need for maternal blood transfusion. However, active management may increase maternal diastolic blood pressure, vomiting after birth, afterpains, use of analgesia from birth up to discharge from the labour ward, and more women returning to hospital with bleeding (outcome not pre-specified).In the comparison of women at low risk of excessive bleeding, there were similar findings, except it was uncertain whether there was a difference identified between groups for severe primary PPH (average RR 0.31, 95% CI 0.05 to 2.17; 2 studies, 2941 women, I2 = 71%), maternal Hb less than 9 g/dL at 24 to 72 hours (average RR 0.17, 95% CI 0.02 to 1.47; 1 study, 193 women) or the need for neonatal admission (average RR 1.02, 95% CI 0.55 to 1.88; 1 study, 1512 women). In this group, active management may make little difference to the rate of neonatal jaundice requiring phototherapy (average RR 1.31, 95% CI 0.78 to 2.18; 1 study, 1447 women).Hypertension and interference with placental transfusion might be avoided by using modifications to the active management package, for example, omitting ergot and deferring cord clamping, but we have no direct evidence of this here.

AUTHORS' CONCLUSIONS

Although the data appeared to show that active management reduced the risk of severe primary PPH greater than 1000 mL at the time of birth, we are uncertain of this finding because of the very low-quality evidence. Active management may reduce the incidence of maternal anaemia (Hb less than 9 g/dL) following birth, but harms such as postnatal hypertension, pain and return to hospital due to bleeding were identified.In women at low risk of excessive bleeding, it is uncertain whether there was a difference between active and expectant management for severe PPH or maternal Hb less than 9 g/dL (at 24 to 72 hours). Women could be given information on the benefits and harms of both methods to support informed choice. Given the concerns about early cord clamping and the potential adverse effects of some uterotonics, it is critical now to look at the individual components of third-stage management. Data are also required from low-income countries.It must be emphasised that this review includes only a small number of studies with relatively small numbers of participants, and the quality of evidence for primary outcomes is low or very low.

New Evidence on Carbetocin: Another Arrow in Our Quiver

Carbetocin is more heat stable than oxytocin with at least equivalent efficacy for preventing postpartum hemorrhage. It will certainly be helpful if the supplier can make it available in low-income country settings at a price comparable to oxytocin. But even so, programs will still need oxytocin and other uterotonic medications.