Epidemiological investigation of a temporal increase in atonic postpartum haemorrhage: a population-based retrospective cohort study

[Cell salvage in obstetrics-Background and practical implementation]

Postpartum hemorrhage (PPH) remains a leading cause of maternal mortality worldwide, with an increasing incidence in western countries over the past decades. During this period the numbers of PPH-related allogeneic red blood cell (RBC) transfusions have also significantly increased. Given the increasing scarcity and risks of allogeneic RBC transfusions, which are also associated with adverse maternal outcomes, optimized blood management strategies are urgently needed in obstetrics. In recent years, patient blood management (PBM) has been increasingly integrated into medical care, resulting in a significant improvement in patient outcomes. Cell salvage (CS) is one of the PBM blood-sparing techniques that enables the collection, processing and retransfusion of the patient's own blood during major bleeding events. Although recent evidence indicates that CS can significantly reduce the demand for allogeneic RBC transfusions and improve patient outcomes, the utilization in obstetrics in German hospitals remains low, with a usage rate of only 0.07% of births with peripartum hemorrhage. It must be assumed that concerns about patient-related complications, such as amniotic fluid embolism and maternal alloimmunization contribute to this hesitancy, alongside a lack of familiarity with the technique. This article provides an overview of the current evidence on the use and safety of CS in obstetrics. To facilitate a practical implementation, fundamental considerations and organizational precautions were prepared based on the experiences of the University Hospitals in Würzburg and Frankfurt and presented in the form of graphics and checklists for the perioperative use of CS during cesarean sections.

Prolonged second stage of labor and risk of postpartum hemorrhage in nullipara with epidural anesthesia and vaginal delivery: A cohort study with propensity score analysis

OBJECTIVE

To conduct an analysis using propensity score methods, exploring the association between a prolonged second stage (>3 h) and the risk of postpartum hemorrhage (PPH) in a diverse population.

METHODS

We conducted a prospective cohort study involving nullipara with epidural anesthesia and vaginal delivery, aged ≥18 years, presenting cephalically, and with a gestational age (GA) of ≥24 weeks at a tertiary maternity hospital in China (chictr.org.cn identifier: ChiCTR2200063094). Women undergoing emergency cesarean section in labor were excluded. The primary outcome was PPH, with secondary outcomes including severe postpartum hemorrhage and blood transfusion. We employed propensity score overlap weighting to analyze the association between prolonged second stage labor and PPH.

RESULTS

The study included 3643 nullipara with epidural anesthesia, comprising 77 with a second stage of labor >3 h and 3566 with a second stage ≤3 h. Utilizing propensity score overlap weighting, there were no significant differences observed between the two groups regarding the risk of PPH (29.87% in >3 h group vs 17.64% in ≤3 h group; weighted odds ratio 1.01; 95% CI: 0.51-2.02). Subgroup interaction tests for PPH were not significant for assisted vaginal delivery, induction of labor, macrosomia, third-/fourth-degree perineal laceration, GA >41 weeks, twin pregnancies, episiotomy and GA >37 weeks. Sensitivity analysis did not reveal significant differences.

CONCLUSION

This study did not find evidence supporting an increased risk of PPH associated with a second stage of labor lasting >3 h in our population, providing additional evidence for clinical practice.

Severe maternal morbidity surveillance, temporal trends and regional variation: A population-based cohort study

OBJECTIVE

To quantify temporal trends and regional variation in severe maternal morbidity (SMM) in Sweden.

DESIGN

Cohort study.

POPULATION

Live birth and stillbirth deliveries in Sweden, 1999-2019.

METHODS

Types and subtypes of SMM were identified, based on a standard list (modified for Swedish clinical setting after considering the frequency and validity of each indicator) using diagnoses and procedure codes, among all deliveries at ≥22 weeks of gestation (including complications within 42 days of delivery). Contrasts between regions were quantified using rate ratios (RRs) and 95% confidence intervals (95% CIs). Temporal changes in SMM types and subtypes were described.

MAIN OUTCOME MEASURES

Types and subtypes of SMM.

RESULTS

There were 59 789 SMM cases among 2 212 576 deliveries, corresponding to 270.2 (95% CI 268.1-272.4) per 10 000 deliveries. Composite SMM rates increased from 236.6 per 10 000 deliveries in 1999 to 307.3 per 10 000 deliveries in 2006, before declining to 253.8 per 10 000 deliveries in 2019. Changes in composite SMM corresponded with temporal changes in severe haemorrhage rates, which increased from 94.9 per 10 000 deliveries in 1999 to 169.3 per 10 000 deliveries in 2006, before declining to 111.2 per 10 000 deliveries in 2019. Severe pre-eclampsia, eclampsia and HELLP (haemolysis, elevated liver enzymes and low platelet count) syndrome (103.8 per 10 000 deliveries), severe haemorrhage (133.7 per 10 000 deliveries), sepsis, embolism, disseminated intravascular coagulation, shock and severe mental health disorders were the most common SMM types. Rates of embolism, disseminated intravascular coagulation and shock, acute renal failure, cardiac complications, sepsis and assisted ventilation increased, whereas rates of surgical complications, severe uterine rupture and anaesthesia complications declined.

CONCLUSIONS

The observed spatiotemporal variations in composite SMM and SMM types provide substantive insights and highlight regional priorities for improving maternal health.

Predictors of Postpartum Hemorrhage and Associated Outcomes at a Midwest Academic Medical Center

Background

Postpartum hemorrhage (PPH) remains a significant cause of maternal morbidity and mortality around the world, with rates increasing in the United States. The objective of this study was to determine predictors of, and outcomes associated with, PPH at a Midwest academic health center.

Methods

Demographic and clinical data were obtained from the electronic medical record on all consecutive delivering patients between May 1, 2020, and April 30, 2021. Associations between PPH and perinatal characteristics and outcomes were assessed using logistic regression models. A significance threshold of 0.05 was used for all comparisons.

Results

Of the 2497 delivering patients during the study period, 437 (18%) experienced PPH. Chronic hypertension, gestational hypertension, and preeclampsia with and without severe features were all associated with increased odds of PPH (odds rations [ORs], respectively, 1.61 (95% CI:1.13-2.24, p = 0.006), 1.62 (95% CI 1.18-2.21, p = 0.003), 1.81 (95% CI 1.14-2.80, p ≤ 0.001), and 1.92 (95% CI 1.29-2.82, p = 0.009). There were also increased odds of PPH with type I diabetes: 2.83 (95% CI 1.45-5.30, p = 0.001), type II diabetes: 2.14 (95% CI 1.15-3.82, p = 0.012), twin delivery: 3.20 (95% CI 2.11-4.81, p ≤ 0.001), cesarean delivery: 5.66 (95% CI 4.53-7.09, p ≤ 0.001), and assisted vaginal delivery: 3.12 (95% CI1.95-4.88, p ≤ 0.001). Infants of mothers with PPH had high odds of NICU admission (CI = 1.34-2.07, p < 0.001) and hypoxic ischemic encephalopathy (CI = 1.64-7.14, p < 0.001).

Conclusion

Our findings confirm previous literature that preexisting and pregnancy-related hypertension, diabetes mellitus, multiple gestation, cesarean delivery, and assisted vaginal delivery are important predictors of PPH. In addition, we found that neonates of mothers with PPH had more adverse outcomes. These results may help to inform clinical care as rates of PPH continue to rise in the United States.

Efficacy and safety of nalbuphine for epidural labor analgesia at high altitude: An observational study

Xining is located at the eastern edge of the Qinghai-Tibet Plateau, with an average altitude of >7000 feet (>2000 m). Nalbuphine is a kappa-opioid receptor agonist that can provide analgesia with fewer side effects than other opioid analgesics. This study aimed to evaluate pain control, side effects, and neonatal outcomes from combining nalbuphine with sufentanil and ropivacaine in 600 women during epidural anesthesia while giving birth at a high altitude in Xining, China. A total of 600 parturients receiving epidural labor analgesia were randomly divided into 2 groups, each group 300 parturients. The nalbuphine group received nalbuphine, sufentanil, and ropivacain, the control group only received sufentanil and ropivacain. The analgesic effect was evaluated through the Visual Analogue Scale scores. Neonatal outcomes were mainly evaluated through the Apgar Scores. Compared to the control group, the nalbuphine group showed lower Visual Analogue Scale scores at all time points after analgesia (P < .05). In comparison with the control group, parturients in the nalbuphine group showed lower incidence rates of fever at delivery, 24-hour postpartum bleeding, and pruritus (P < .05). However, between the 2 groups, there were no statistically significant differences in the remaining maternal and infant outcomes and neonatal outcomes (P > .05). Moreover, no adverse effects on neonatal outcomes were observed. The findings from this study support findings from previous studies that nalbuphine provided safe epidural analgesia without significant side effects for the mother and infant, and showed both safety and efficacy when used during labor at high altitude.

Trends in postpartum hemorrhage and manual removal of the placenta and the association with childbirth interventions: A Dutch nationwide cohort study

BACKGROUND

Because the cause of increasing rates of postpartum hemorrhage (PPH) and manual placental removal (MROP) is still unknown, we described trends in PPH, MROP, and childbirth interventions and examined factors associated with changes in rates of PPH and MROP.

METHODS

This nationwide cohort study used national perinatal registry data from 2000 to 2014 (n = 2,332,005). We included births of women who gave birth to a term singleton child in obstetrician-led care or midwife-led care. Multivariable logistic regression analyses were used to examine associations between characteristics and interventions, and PPH ≥ 1000 mL and MROP.

RESULTS

PPH rates increased from 4.3% to 6.6% in obstetrician-led care and from 2.5% to 4.8% in midwife-led care. MROP rates increased from 2.4% to 3.4% and from 1.0% to 1.4%, respectively. A rising trend was found for rates of induction and augmentation of labor, pain medication, and cesarean section, while rates of episiotomy and assisted vaginal birth declined. Adjustments for characteristics and childbirth interventions did not result in large changes in the trends of PPH and MROP. After adjustments for childbirth interventions, in obstetrician-led care, the odds ratio (OR) of PPH in 2014 compared with the reference year 2000 changed from 1.66 (95% CI 1.57-1.76) to 1.64 (1.55-1.73) among nulliparous women and from 1.56 (1.47-1.66) to 1.52 (1.44-1.62) among multiparous women. For MROP, the ORs changed from 1.51 (1.38-1.64) to 1.36 (1.25-1.49) and from 1.56 (1.42-1.71) to 1.45 (1.33-1.59), respectively.

CONCLUSIONS

Rising PPH trends were not associated with changes in population characteristics and rising childbirth intervention rates. The rising MROP was to some extent associated with rising intervention rates.

Association between duration of intrapartum oxytocin exposure and obstetric hemorrhage

PURPOSE

Prolonged duration of intrapartum oxytocin exposure is included as a risk factor within widely adopted obstetric hemorrhage risk stratification tools. However, the duration of exposure that confers increased risk is poorly understood. This study aimed to assess the association between duration of intrapartum oxytocin exposure and obstetric blood loss, as measured by quantitative blood loss, and hemorrhage-related maternal morbidity.

METHODS

This was a retrospective cohort study of all deliveries from 2018 to 2019 at a single medical center. We included patients who had received any intrapartum oxytocin, and we categorized them into 1 of 5 groups: > 0-2, ≥ 2-4, ≥ 4-6, ≥ 6-12, and ≥ 12 h of intrapartum oxytocin exposure. The primary outcomes were mean quantitative blood loss, proportion with obstetric hemorrhage (defined as quantitative blood loss ≥ 1000 mL), and proportion with obstetric hemorrhage-related morbidity, a composite of hemorrhage-related morbidity outcomes. Secondary outcomes were hemorrhage-related pharmacologic and procedural interventions. A stratified analysis was also conducted to examine primary and secondary outcomes by delivery mode.

RESULTS

Of 5332 deliveries between January 1, 2018 and December 31, 2019 at our institution, 2232 (41.9%) utilized oxytocin for induction or augmentation. 326 (14.6%) had exposure of > 0-2 h, 295 (13.2%) ≥ 2-4 h, 298 (13.4%) ≥ 4-6 h, 562 (25.2%) ≥ 6-12 h, and 751 (33.6%) ≥ 12 h. Across all deliveries, there was higher mean quantitative blood loss (p < 0.01) as well as increased odds of obstetric hemorrhage (adjusted odds ratio [aOR] 1.52, 95% confidence interval [CI] 1.21-1.91) for those with ≥ 12 h of oxytocin compared to all groups between > 0-12 h of exposure. In our stratified analysis, ≥ 12 h of oxytocin exposure was associated with higher mean quantitative blood loss (p = 0.04) and odds of obstetric hemorrhage in vaginal deliveries (aOR 1.47, 95% CI: 1.03-2.11), though not in cesarean deliveries (aOR 1.16, 95% CI 0.82-1.62). There were no differences in proportion with obstetric hemorrhage-related morbidity across all deliveries (p = 0.40) or in the stratified analysis.

CONCLUSION

Intrapartum oxytocin exposure of ≥ 12 h was associated with increased quantitative blood loss and odds of obstetric hemorrhage in vaginal, but not cesarean, deliveries.

Family history of postpartum hemorrhage is a risk factor for postpartum hemorrhage after vaginal delivery: results from the French prospective multicenter Haemorrhages and Thromboembolic Venous Disease of the Postpartum cohort study

BACKGROUND

Postpartum hemorrhage is a major component of perinatal morbidity and mortality that affects young women worldwide and is still often unpredictable. Reducing the incidence of postpartum hemorrhage is a major health issue and identifying women at risk for postpartum hemorrhage is a key element in preventing this complication.

OBJECTIVE

This study aimed to estimate postpartum hemorrhage prevalence after vaginal delivery and to identify postpartum hemorrhage risk factors.

STUDY DESIGN

Unselected pregnant women ≥16 years of age admitted to 1 of 6 maternity wards in Brittany (France) for vaginal birth after 15 weeks of gestation were recruited in this prospective, multicenter cohort study between June 1, 2015, and January 31, 2019. Postpartum hemorrhage was defined as blood loss ≥500 mL in the 24 hours following delivery. Independent risk factors for postpartum hemorrhage were determined using logistic regression. Missing data were imputed using the Multivariate Imputation by Chained Equations method.

RESULTS

Among 16,382 included women, the postpartum hemorrhage prevalence was 5.37%. A first-degree family history of postpartum hemorrhage (adjusted odds ratio, 1.63; 95% confidence interval, 1.24-2.14) and a personal transfusion history (adjusted odds ratio, 1.90; 95% confidence interval, 1.23-2.92) were significantly associated with postpartum hemorrhage. The use of oxytocin during labor was also a risk factor for postpartum hemorrhage (adjusted odds ratio, 1.24; 95% confidence interval, 1.06-1.44). Inversely, smoking during pregnancy and intrauterine growth restriction were associated with a reduced risk for postpartum hemorrhage (adjusted odds ratio, 0.76; 95% confidence interval, 0.63-0.91, and 0.34; 95% confidence interval, 0.13-0.87, respectively).

CONCLUSION

In addition to classical risk factors, this study identified a family history of postpartum hemorrhage and personal transfusion history as new characteristics associated with postpartum hemorrhage after vaginal delivery. The association of postpartum hemorrhage with a family history of postpartum hemorrhage suggests a hereditary hemorrhagic phenotype and calls for genetic studies. Identifying women at risk for postpartum hemorrhage is a key element of being prepared for this complication.

Procedural techniques to control postpartum hemorrhage

Postpartum hemorrhage can occur unexpectedly and with high dynamics. The mother's life often depends on quick action and good communication within an interdisciplinary team. Knowledge of each other's therapeutic options plays a major role. Treatment procedures include obstetric, surgical, and radiologic techniques. In addition to availability and experience with the techniques, two important aspects must be considered in the selection process: the type of delivery and the cause of the hemorrhage. In particular, the distinction between pregnancies with or without disturbed placentation from the placenta accreta spectrum is crucial. From these two points of view, we discuss here different uterus-preserving and uterus-removing techniques. We describe in detail the advantages and disadvantages of each procedure. Because most therapeutic options are based on small case series and uncontrolled studies, local circumstances and physician experience are critical in setting internal standards.

Epidemiology and definition of PPH worldwide

Postpartum/peripartum hemorrhage (PPH) is an obstetric emergency complicating 1-10% of all deliveries and is a leading cause of maternal mortality and morbidity worldwide. However, the incidence of PPH differs widely according to the definition and criteria used, the way of measuring postpartum blood loss, and the population being studied with the highest numbers in developing countries. Despite all the significant progress in healthcare, the incidence of PPH is rising due to an incomplete implementation of guidelines, resulting in treatment delays and suboptimal care. A consensus clinical definition of PPH is needed to enable awareness, early recognition, and initiation of appropriate intensive treatment. Unfortunately, the most used definition of PPH based on blood loss ≥500 ml after delivery suffers from inaccuracies in blood loss quantification and is not clinically relevant in most cases, as the amount of blood loss does not fully reflect the severity of bleeding.

Risk factors and recurrence of cause-specific postpartum hemorrhage: A population-based study

OBJECTIVE

To explore risk profiles of the different types of postpartum hemorrhage (PPH >500ml or severe PPH >1500ml) and their recurrence risks in a subsequent delivery.

METHODS

With data from The Medical Birth Registry of Norway and Statistics Norway we performed a population-based cohort study including all singleton deliveries in Norway from 1967-2017. Multilevel logistic regression was used to calculate odds ratio (OR), with 95% confidence interval (CI), with different PPH types (PPH >500ml or PPH >1500ml (severe PPH) combined with retained placenta, uterine atony, obstetric trauma, dystocia, or undefined cause) as outcomes.

RESULT

We identified 277 746 PPH cases of a total of 3 003 025 births (9.3%) from 1967 to 2017. Retained placenta (and/or membranes) was most often registered as severe PPH (29.3%). Maternal, fetal, and obstetric characteristics showed different associations with the PPH types. Male sex of the neonate was associated with reduced risk of PPH. This effect was strongest on PPH due to retained placenta (adjusted OR, (aOR): 0.80, 95% CI 0.78-0.82), atony (aOR 0.92, 95% CI: 0.90-0.93) and PPH with undefined cause (aOR 0.96, 95% CI: 0.95-0.97). Previous cesarean section showed a strong association with PPH due to dystocia (aOR of 13.2, 95% CI: 12.5-13.9). Recurrence risks were highest for the same type: PPH associated with dystocia (aOR: 6.8, 95% CI: 6.3-7.4), retained placenta and/or membranes (aOR: 5.9, 95% CI: 5.5-6.4), atony (aOR: 4.0, 95% CI: 3.8-4.2), obstetric trauma (aOR: 3.9, 95% CI: 3.5-4.3) and PPH of undefined cause (aOR: 2.2, 95% CI: 2.1-2.3).

CONCLUSION

Maternal, fetal and obstetric characteristics had differential effects on types of PPH. Recurrence differed considerably between PPH types. Retained placenta was most frequently registered with severe PPH, and showed strongest effect of sex; delivery of a boy was associated with lower risk of PPH. Previous cesarean increased the risk of PPH due to dystocia.

Determining the incidence of postpartum haemorrhage among Ontario women with and without inherited bleeding disorders: A population-based cohort study

INTRODUCTION

At a population level, there is a poor understanding of the incidence and pre-disposing risk factors of postpartum haemorrhage (PPH) among women with inherited bleeding disorders (IBD).

AIM

To determine the incidence of PPH, and identify maternal factors associated with risk of PPH among women with IBD.

METHODS

We conducted a retrospective cohort study using data housed within ICES (formerly known as the Institute for Clinical Evaluative Sciences). The cohort included women with an in-hospital, live or stillborn delivery, between January 2014 and December 2019. The primary outcome was PPH (identified by ICD-10 code O72). PPH incidence and risk factors were compared between women with and without IBD. Temporal trends were assessed using the Cochrane-Armitage test. Between group differences were assessed using standardised differences (std. difference).

RESULTS

Total 601,773 women were included; 2002 (.33%) had an IBD diagnosis. PPH incidence was 1.5 times higher (7.3 vs. 4.9 cases/100 deliveries, std. difference .1) among women with IBD compared to women without. Women with IBD were slightly older (31.7 vs. 30.7 years), had higher rates of hypertension, previous PPH, and induction of labour. Women with IBD were more frequently diagnosed with anaemia (4.8% vs. 1.8%; std difference .17) and had lower haemoglobin levels at admission for delivery compared to women without IBD.

CONCLUSIONS

This study contributes to the literature regarding obstetric bleeding among women with IBD, showing that anaemia at delivery may be an important risk factor for PPH. Given their predisposition to anaemia, clarifying this relationship will optimise management and outcomes.

Postpartum hemorrhage in women with von Willebrand disease: Consider other etiologies

OBJECTIVE

Higher rates of postpartum hemorrhage (PPH) have been reported for women with von Willebrand disease (VWD). Comprehensive multidisciplinary care reduces these rates; thus PPH may not be secondary to VWD.

METHODS

We conducted a retrospective review for the period of 2009-2018, including all VWD pregnancies at two tertiary care academic hospitals to determine rates, etiology, and timing of PPH.

RESULTS

A total of 63 women with 80 pregnancies were included. Three women had twin pregnancies. Sixty-six pregnancies (82.5%) involved type 1 VWD; 4 (5.0%), type 2 (unclear subtype); 3 (3.8%) type 2A; 3 (3.8%) type 2B; and 2 (2.5%), type 2M. Median age of patients was 32.9 years (range 19-43 y). Most patients were blood type O (65%), and 33 of 80 preganancies (41.3%) were nulliparous. The mean bleeding assessment score was 8 (range 0-16). Thirty-seven pregnancies (46.3%) received prophylactic hemostatic treatment prior to delivery. Seventy-four percent of pregnancies were delivered vaginally, and 88% received epidural anaesthesia. The majority of pregnancies (78.8%) had von Willebrand factor (VWF) levels assessed during the third trimester, with most (71.3%) achieving VWF levels above 1.00 IU/mL. Four pregnancies (5.2%) were complicated by primary PPH; uterine atony in 2 and placenta previa in 1. Delayed postpartum bleeding occurred in 5 pregnancies (6.3%).

CONCLUSION

Multidisciplinary care of pregnancies with VWD improves outcomes. Rates of primary and delayed PPH in this study are lower than previously described and are similar to those of women without VWD. In women with VWD, uterine etiologies for primary PPH need to be considered, in a manner similar to the assessment of women without VWD, to ensure hemostasis is achieved.

A comprehensive digital phenotype for postpartum hemorrhage

OBJECTIVE

We aimed to establish a comprehensive digital phenotype for postpartum hemorrhage (PPH). Current guidelines rely primarily on estimates of blood loss, which can be inaccurate and biased and ignore complementary information readily available in electronic medical records (EMR). Inaccurate and incomplete phenotyping contributes to ongoing challenges in tracking PPH outcomes, developing more accurate risk assessments, and identifying novel interventions.

MATERIALS AND METHODS

We constructed a cohort of 71 944 deliveries from the Mount Sinai Health System. Estimates of postpartum blood loss, shifts in hematocrit, administration of uterotonics, surgical interventions, and diagnostic codes were combined to identify PPH, retrospectively. Clinical features were extracted from EMRs and mapped to common data models for maximum interoperability across hospitals. Blinded chart review was done by a physician on a subset of PPH and non-PPH patients and performance was compared to alternate PPH phenotypes. PPH was defined as clinical diagnosis of postpartum hemorrhage documented in the patient's chart upon chart review.

RESULTS

We identified 6639 PPH deliveries (9% prevalence) using our phenotype-more than 3 times as many as using blood loss alone (N = 1,747), supporting the need to incorporate other diagnostic and intervention data. Chart review revealed our phenotype had 89% accuracy and an F1-score of 0.92. Alternate phenotypes were less accurate, including a common blood loss-based definition (67%) and a previously published digital phenotype (74%).

CONCLUSION

We have developed a scalable, accurate, and valid digital phenotype that may be of significant use for tracking outcomes and ongoing clinical research to deliver better preventative interventions for PPH.

Iron Deficiency Anaemia and Atonic Postpartum Haemorrhage Following Labour

The purpose of this retrospective cohort study is to determine if iron deficiency anaemia (IDA) is associated with increased atonic postpartum haemorrhage (PPH) following labour. Women with singleton pregnancy carried to 24 or more weeks gestation, who were delivered under our care from 1997 to 2019, constituted the study population. A diagnosis of IDA was based on the finding of haemoglobin <10 g/dL and serum ferritin <15 μg/L in the absence of haemoglobinopathies. Women with elective caesarean section were excluded. Maternal characteristics, use of oxytocin, labour outcome and occurrence of PPH were compared between women with and without a diagnosis of IDA. The 1032 women (0.86%) with IDA exhibited slightly but significantly different maternal characteristics and had significantly higher incidence of total (4.5% versus 3.2%, p = 0.024) and atonic PPH (3.1% versus 2.0%, p = 0.011) despite similar incidences of labour induction, augmentation, and instrumental and intrapartum caesarean delivery. Multivariate analysis with adjustment for the effects of age, body mass index, height, parity, abortion history, labour induction and augmentation, instrumental delivery and infant macrosomia demonstrated that IDA was independently associated with total PPH (adjusted relative risk, aRR: 1.455, 95% confidence ratio, CI: 1.040-2.034) and atonic PPH (aRR: 1.588, 95% CI: 1.067-2.364). Our results indicate that despite the low prevalence in our population, IDA was independently associated with atonic PPH, probably consequent to placental adaptive changes in the presence of IDA. The correction and prevention of IDA could be the most important measure in countering the rising global prevalence of atonic PPH.

Tranexamic acid for the prevention and the treatment of primary postpartum haemorrhage: a systematic review

Tranexamic acid (TA) has been proposed for preventing or treating primary postpartum haemorrhage (PPH), which is the leading cause of maternal morbidity and mortality worldwide. We conducted a systematic literature search to the TA role in managing PPH in vaginal and caesarean delivery. Twenty-seven randomised controlled trials (RCTs) (33,302 women) were identified. Three RCTs investigated TA for preventing PPH after vaginal delivery and 22 after caesarean section. None demonstrated a preventive effect on secondary clinical outcomes related to blood loss. Two trials evaluated TA for treating PPH after vaginal and caesarean delivery. Only the WOMAN trial showed that 1 g of TA is effective. In conclusion, TA is considered useful and is recommended or advised for treating PPH. Conversely, available evidence on the prophylactic role is still limited, and this use is not supported. Further investigation is recommended. In this regard, stronger and more reliable outcomes than blood loss should be considered.

Cost-effectiveness analysis of carbetocin versus oxytocin for the prevention of postpartum hemorrhage following vaginal birth in the United Kingdom

AIMS

To assess the cost-effectiveness of carbetocin versus oxytocin for the prevention of postpartum hemorrhage (PPH) following vaginal birth from the perspective of the UK National Health Service (NHS).

MATERIALS AND METHODS

A decision tree model was designed to analyze the cost per PPH event avoided associated with utilizing carbetocin versus oxytocin for prophylactic treatment of PPH in women following vaginal birth from a UK perspective. It modelled the potential for women to require an additional uterotonic after prophylaxis, and to still experience a PPH event and receive associated treatment. Inpatient recovery and follow-up periods post-PPH were also included in the model. Costs associated with drug acquisition and administration, PPH management (i.e. additional staffing and possible operating theater and high dependency unit utilization), inpatient hospitalization, and follow-up visits were all considered. Adverse event management costs were not included. Resource utilization varied depending on the severity of the PPH event (as defined by the amount of blood lost). PPH events avoided were estimated. In an exploratory analysis, quality adjusted life years (QALYs) were estimated as well.

RESULTS

In the deterministic base case, costs were £55 lower and PPH events were 0.0342 lower per woman with carbetocin use compared to oxytocin use. Across the cohort of 100 women the reduction in PPH events led to the largest cost savings (£4,233 saved) out of all cost categories, with total cost savings of £5,495. Carbetocin utilization amongst the entire cohort led to 3.42 avoided PPH events compared to oxytocin utilization, comprised of 3.03 fewer mild/moderate PPH events and 0.39 fewer severe PPH events. Carbetocin utilization led to 0.0001 additional QALYs per woman.

CONCLUSION

Carbetocin utilization leads to lower prophylactic treatment costs and less PPH events versus oxytocin when utilized for the prevention of PPH following vaginal birth in the UK.

Incidence and Risk Factors of Postpartum Hemorrhage in China: A Multicenter Retrospective Study

Background: Postpartum hemorrhage (PPH) is a leading cause of maternal morbidity and mortality worldwide but the incidence and its risk factors in China is limited. The objective of this study is to investigate the incidence and the risk factors of PPH in Chinese women.

Methods: A multi-center retrospective study of pregnant women at ≥28 weeks of gestation was conducted. Logistic regression was used to identify potential risk factors of PPH and receiver operating characteristic curve was used to evaluate the predictive performance of the identified risk factors. Subgroup analysis focusing on the number of fetus and the mode of delivery was conducted.

Results: A total of 99,253 pregnant women were enrolled and 804 (0.81%) experienced PPH. The subgroup analysis revealed that the incidence of PPH was 0.75, 2.65, 1.40, and 0.31% in singletons, twin pregnancies, cesarean sections, and vaginal deliveries, respectively. Placenta previa and placenta accreta were the predominant risk factors of PPH in the overall population and all subgroups. A twin pregnancy was a risk factor for PPH regardless of the mode of delivery. Obesity, and multiparity were risk factors for PPH in both singletons and cesarean section cases, but the latter predicted a reduced probability of PPH in vaginal deliveries. Macrosomia was associated with increased risk of PPH in singletons or vaginal deliveries. In women who delivered vaginally, preeclampsia was associated with a higher risk of PPH. The areas under the curve for the overall cohort, singletons, twin pregnancies, cesarean section cases, and vaginal deliveries were 0.832 (95% confidence interval [CI] 0.813–0.851), 0.824 (95% CI 0.803–0.845), 0.686 (95% CI 0.617–0.755), 0.854 (95% CI 0.834–0.874), and 0.690 (95% CI 0.646–0.735), respectively.

Conclusions: The risk factors of PPH varied slightly based on the number of fetuses and the mode of delivery, while placenta previa and placenta accreta were the two major risk factors. A combination of the identified risk factors yielded a satisfactory predictive performance in determining PPH in the overall cohort, singletons pregnancies, and women who delivered by cesarean section, whereas the performance was moderate in twin pregnancies and in women delivering vaginally.

Is the increase in postpartum hemorrhage after vaginal birth because of altered clinical practice?: A register-based cohort study

BACKGROUND

To identify risk factors for severe postpartum hemorrhage (PPH) ≥1000 ml in women giving birth vaginally.

METHOD

A register-based cohort study including women with singleton pregnancies giving birth vaginally at term to a live-born child at Aarhus University Hospital, Denmark, from January 1, 2004, to December 31, 2012. Logistic multivariable regression was used to analyze data.

RESULTS

In 31 837 births, 1832 women (5.7%) experienced severe PPH. Maternal age, smoking during pregnancy, and prepregnancy body mass index did not increase the risk of severe PPH. However, nulliparous and multiparous women with a previous cesarean birth had an increased risk of severe PPH. Antepartum and intrapartum risk factors for severe PPH included gestational age >40 weeks, induction of labor, augmentation of labor, irregular fetal position, instrumental birth, and birthweight >4000 g. In particular, the combination of induction and augmentation of labor doubled the risk of severe PPH. Among genital tract tears, vaginal tears >3 cm were associated with the highest risk of severe PPH.

CONCLUSIONS

Maternal characteristics did not increase the risk of severe PPH, except for nulliparous and multiparous women with a previous cesarean birth. Obstetric interventions such as induction of labor, augmentation of labor, and a birthweight higher than 4000 g increased the risk of severe PPH. Larger vaginal tears presented the highest risk of severe PPH. Clinical practice with rigorous indications for obstetric interventions and timely identification and management of genital tract tears may reduce risk of severe PPH.

Association of Gestational Age with Postpartum Hemorrhage: An International Cohort Study

BACKGROUND

Risk factors for postpartum hemorrhage, such as chorioamnionitis and multiple gestation, have been identified in previous epidemiologic studies. However, existing data describing the association between gestational age at delivery and postpartum hemorrhage are conflicting. The aim of this study was to assess the association between gestational age at delivery and postpartum hemorrhage.

METHODS

The authors conducted a population-based retrospective cohort study of women who underwent live birth delivery in Sweden between 2014 and 2017 and in California between 2011 and 2015. The primary exposure was gestational age at delivery. The primary outcome was postpartum hemorrhage, classified using International Classification of Diseases, Ninth Revision-Clinical Modification codes for California births and a blood loss greater than 1,000 ml for Swedish births. The authors accounted for demographic and obstetric factors as potential confounders in the analyses.

RESULTS

The incidences of postpartum hemorrhage in Sweden (23,323/328,729; 7.1%) and in California (66,583/2,079,637; 3.2%) were not comparable. In Sweden and California, the incidence of postpartum hemorrhage was highest for deliveries between 41 and 42 weeks' gestation (7,186/75,539 [9.5%] and 8,921/160,267 [5.6%], respectively). Compared to deliveries between 37 and 38 weeks, deliveries between 41 and 42 weeks had the highest adjusted odds of postpartum hemorrhage (1.62 [95% CI, 1.56 to 1.69] in Sweden and 2.04 [95% CI, 1.98 to 2.09] in California). In both cohorts, the authors observed a nonlinear (J-shaped) association between gestational age and postpartum hemorrhage risk, with 39 weeks as the nadir. In the sensitivity analyses, similar findings were observed among cesarean deliveries only, when postpartum hemorrhage was classified only by International Classification of Diseases, Tenth Revision-Clinical Modification codes, and after excluding women with abnormal placentation disorders.

CONCLUSIONS

The postpartum hemorrhage incidence in Sweden and California was not comparable. When assessing a woman's risk for postpartum hemorrhage, clinicians should be aware of the heightened odds in women who deliver between 41 and 42 weeks' gestation.

EDITOR’S PERSPECTIVE

Literature Review: Physiological Management for Preventing Postpartum Hemorrhage

The aim of this paper was to summarize the existing literature regarding postpartum hemorrhage (PPH) and its physiological management (i.e., skin-to-skin contact and breastfeeding). The background surrounding PPH and the role of skin-to-skin contact (SSC) and breastfeeding (BF) in PPH are identified, and these interventions are supported as a crucial means of preventing or minimizing the incidence of PPH. Despite its importance, to the best of my knowledge, an evaluation of this relationship has not yet been undertaken. The narrative literature review approach was used to summarize topic related researches. The search included three databases: CINAHL, PubMed, and Google Scholar. All articles related to the role of SSC and BF in PPH were chosen from the different databases. The findings demonstrate that SSC and BF are cost-effective methods that could be considered practices for the prevention of PPH. Immediate Skin-to-skin contact (SSC) and breastfeeding (BF) are central mediators of the psychophysiological process during the first hour after delivery (the third and fourth stages of labor).

How to specify healthcare process improvements collaboratively using rapid, remote consensus-building: a framework and a case study of its application

BACKGROUND

Practical methods for facilitating process improvement are needed to support high quality, safe care. How best to specify (identify and define) process improvements - the changes that need to be made in a healthcare process - remains a key question. Methods for doing so collaboratively, rapidly and remotely offer much potential, but are under-developed. We propose an approach for engaging diverse stakeholders remotely in a consensus-building exercise to help specify improvements in a healthcare process, and we illustrate the approach in a case study.

METHODS

Organised in a five-step framework, our proposed approach is informed by a participatory ethos, crowdsourcing and consensus-building methods: (1) define scope and objective of the process improvement; (2) produce a draft or prototype of the proposed process improvement specification; (3) identify participant recruitment strategy; (4) design and conduct a remote consensus-building exercise; (5) produce a final specification of the process improvement in light of learning from the exercise. We tested the approach in a case study that sought to specify process improvements for the management of obstetric emergencies during the COVID-19 pandemic. We used a brief video showing a process for managing a post-partum haemorrhage in women with COVID-19 to elicit recommendations on how the process could be improved. Two Delphi rounds were then conducted to reach consensus.

RESULTS

We gathered views from 105 participants, with a background in maternity care (n = 36), infection prevention and control (n = 17), or human factors (n = 52). The participants initially generated 818 recommendations for how to improve the process illustrated in the video, which we synthesised into a set of 22 recommendations. The consensus-building exercise yielded a final set of 16 recommendations. These were used to inform the specification of process improvements for managing the obstetric emergency and develop supporting resources, including an updated video.

CONCLUSIONS

The proposed methodological approach enabled the expertise and ingenuity of diverse stakeholders to be captured and mobilised to specify process improvements in an area of pressing service need. This approach has the potential to address current challenges in process improvement, but will require further evaluation.

Characterising and describing postpartum haemorrhage emergency kits in context: a protocol for a mixed-methods study

INTRODUCTION

Postpartum haemorrhage (PPH) is an obstetric emergency requiring prompt and accurate response. PPH emergency kits containing equipment and medications can facilitate this kind of intervention, but their design and contents vary, potentially introducing risk of confusion or delay. Designs may be suboptimal, and relying on localised kit contents may result in supply chain costs, increased waste and missed opportunities for economies of scale. This study aims to characterise contextual influences on current practice in relation to PPH kits and to describe the range of kits currently employed in UK maternity units.

METHODS AND ANALYSIS

This mixed-methods study comprises two phases. The first will use field observations and semistructured interviews to research PPH kits in a small number (3-5) of maternity units that will be selected to represent diversity. Analysis will be conducted both using an established human factors and ergonomics framework and using the constant comparative method for qualitative data analysis. The second phase will use a research and development platform (Thiscovery) to conduct a crowdsourced photography-based audit of PPH kits currently in use in the UK. Participants will tag images to indicate which objects have been photographed. Quantitative analysis will report the frequency of inclusion of each item in kits and the content differences between kit and unit types. All maternity units in the UK will be invited to take part, with additional targeted recruitment strategies used, if necessary, to ensure that the final sample includes different maternity unit types, sizes and PPH kit types. Study results will inform future work to develop consensus on effective PPH kit designs.

ETHICS AND DISSEMINATION

Approval has been received from the UK Health Research Authority (project ID 274147). Study results will be reported through the research institute's website, presented at conferences and published in peer-reviewed journals.

Risk Factors for Atonic Postpartum Hemorrhage: A Systematic Review and Meta-analysis

OBJECTIVE

To identify and quantify risk factors for atonic postpartum hemorrhage.

DATA SOURCES

PubMed, CINAHL, EMBASE, Web of Science, and and ClinicalTrials.gov databases were searched for English language studies with no restrictions on date or location. Studies included randomized trials, prospective or retrospective cohort studies, and case-control studies of pregnant patients who developed atonic postpartum hemorrhage and reported at least one risk factor.

METHODS OF STUDY SELECTION

Title, abstract, and full-text screening were performed using the Raayan web application. Of 1,239 records screened, 27 studies were included in this review. Adjusted or unadjusted odds ratios (ORs), relative risks, or rate ratios were recorded or calculated. For each risk factor, a qualitative synthesis of low and moderate risk of bias studies classifies the risk factor as definite, likely, unclear, or not a risk factor. For risk factors with sufficiently homogeneous definitions and reference ranges, a quantitative meta-analysis of low and moderate risk of bias studies was implemented to estimate a combined OR.

TABULATION, INTEGRATION, AND RESULTS

Forty-seven potential risk factors for atonic postpartum hemorrhage were identified in this review, of which 15 were judged definite or likely risk factors. The remaining 32 assessed risk factors showed no association with atonic postpartum hemorrhage or had conflicting or unclear evidence.

CONCLUSION

A substantial proportion of postpartum hemorrhage occurs in the absence of recognized risk factors. Many risk factors for atonic hemorrhage included in current risk-assessment tools were confirmed, with the greatest risk conferred by prior postpartum hemorrhage of any etiology, placenta previa, placental abruption, uterine rupture, and multiple gestation. Novel risk factors not currently included in risk-assessment tools included hypertension, diabetes, and ethnicity. Obesity and magnesium were not associated with atonic postpartum hemorrhage in this review.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42020157521.

Factors Associated with Failure of Bakri Balloon Tamponade for the Management of Postpartum Haemorrhage. Case Series Study and Systematic Review

Background: Postpartum haemorrhage (PPH) is an unpredictable obstetric emergency that requires a multidisciplinary approach. Bakri balloon tamponade (BBT) is recommended when PPH does not respond to medical treatment. Nowadays few published studies have performed a multivariate analysis to determine the variables independently associated with BBT failure. Methods: Our study purpose was to determine the variables independently associated with BBT failure: first, in a large single-centre cohort study between 2010 and 2020, and second, in a systematic literature review using Medline and the Cochrane Library. Maternal and perinatal variables, PPH characteristics, technique-related variables and complications were recorded in the case series study, comparing between successful and failed BBT patients. Study characteristic and variables significantly associated with BBT failure were recorded in the systematic review. All studies used a logistic regression test. Results: The case series included 123 patients. The profile of these patients were primiparous, with vaginal delivery and a full-term new-born. BBT was successful in 81.3% of cases. Five studies were included in the systematic review, providing data from 551 patients. BBT was successful in 79.5% of cases. Conclusions: Maternal age, caesarean delivery, ≥7 red blood cells units (RBCU) transfused and curettage before BBT insertion, history of caesarean section, pre-pregnancy obesity, anteriorly placed placenta, placenta accreta, caesarean delivery, estimated blood loss before insertion of BBT, long operation duration, and coagulopathy were independent factors for BBT failure.

A Swedish register-based study exploring primary postpartum hemorrhage in 405 936 full term vaginal births between 2005 and 2015

OBJECTIVE

To explore diagnoses of postpartum haemorrhage following vaginal birth, in relation to socio-demographic and obstetrical data from women who gave birth at term, in Sweden, during the years 2005-2015.

STUDY DESIGN

A register-based cohort study was carried out, describing and comparing socio-demographic variables, obstetric variables and infant variables in 52 367 cases of diagnosed postpartum haemorrhage compared to 353 569 controls without a postpartum haemorrhage diagnosis. Postpartum hemorrhage was identified in The Swedish Medical Birth Register by ICD-10 code O72. Variables for maternal characteristics were dichotomized and used to calculate odds ratios to find possible explanatory variables for postpartum haemorrhage.

RESULTS

Between 2005 and 2015 there was no statistically significant decrease in diagnoses of postpartum haemorrhage after vaginal birth at term. Primiparity was associated with the highest risk and women birthing their fifth or subsequent child were associated with the lowest risk of postpartum hemorrhage. Increased maternal age (> 35 years) and/or obesity (BMI > 30) were associated with higher odds of postpartum haemorrhage. The risk of postpartum hemorrhage was 55 % higher when vaginal birth followed induction as compared to vaginal birth after spontaneous onset. Some of the factors known to be associated with postpartum haemorrhage were poorly documented in The Swedish Medical Birth Register.

CONCLUSIONS

Birthing women in a Swedish contemporary setting are, despite efforts to improve care, still at risk of birth being complicated by postpartum haemorrhage. Primiparity, increasing maternal age and/or obesity are found to provoke an increased risk and the reasons for these findings need to be further investigated. However, grand multi-parity did not increase the risk for postpartum hemorrhage. Codes for diagnoses require correct documentation in the birth records: only when local statistics are sound and correctly reported can intrapartum care be improved, and the incidence of postpartum haemorrhage reduced.

Incidences of Atonic Postpartum Hemorrhage and Related Risk Factors at a Tertiary Hospital in Saudi Arabia

Background: In 2017, there were 295,000 maternal deaths worldwide from preventable causes related to birth. The leading cause of maternal mortality is obstetric hemorrhage. In Saudi Arabia, a paucity of evidence about incidences of atonic Postpartum Hemorrhage (PPH) and related risk factors exists. Therefore, aims were to (a) identify incidences of atonic PPH from 2015 to 2018 (b) determine risk factors of atonic PPH in vaginal birth. Methods: Retrospective chart review with purposive sampling conducted revealed 386 charts, 220 (57%) vaginal birth and 166 (43%) caesarian section (CS). Logistic regression analysis was used. Results: Incidences of atonic PPH were 2.5% from 2015 to 2017, with the rate increasing by 12% from 2017 to 2018. In vaginal birth, significant associations between the severity of blood loss with epidural (F = 6.314, df = 1, p = 0.013), episiotomy (F = 4.38, df = 1, p = 0.038), induction of labor (IOL) (F = 1.224, df = 1, p = 0.004), and Interaction between IOL, AUG, and epidural (F = 7.24, df = 1, p = 0.041) found. Discussion: Increasing rate of atonic PPH confirmed. Epidural, episiotomy, induction of labor, and induction with augmentation are factors associated with severe atonic PPH in vaginal birth.

Oxytocin at elective caesarean delivery: a dose-finding study in women with obesity

Prophylactic oxytocin administration at the third stage of labour reduces blood loss and the need for additional uterotonic drugs. Obesity is known to be associated with an increased risk of uterine atony and postpartum haemorrhage. It is unknown whether women with obesity require higher doses of oxytocin in order to achieve adequate uterine tone after delivery. The purpose of this study was to establish the bolus dose of oxytocin required to initiate effective uterine contraction in 90% of women with obesity (the ED₉₀ ) at elective caesarean delivery. We conducted a double-blind dose-finding study using the biased coin up-down design method. Term pregnant women with a BMI ≥ 40 kg.m^-2 undergoing elective caesarean delivery under regional anaesthesia were included. Those with conditions predisposing to postpartum haemorrhage were not included. Oxytocin was administered as an intravenous bolus over 1 minute upon delivery of the fetus. With the first woman receiving 0.5 IU, oxytocin doses were administered according to a sequential allocation scheme. The primary outcome measure was satisfactory uterine tone, as assessed by the operating obstetrician 2 minutes after administration of the oxytocin bolus. Secondary outcomes included the need for rescue uterotonic drugs, adverse effects and estimated blood loss. We studied 30 women with a mean (SD) BMI of 52.3 (7.6) kg.m^-2 . The ED₉₀ for oxytocin was 0.75 IU (95%CI 0.5-0.93 IU) by isotonic regression and 0.78 IU (95%CI 0.68-0.88 IU) by the Dixon and Mood method. Our results suggest that women with a BMI ≥ 40 kg.m^-2 require approximately twice as much oxytocin as those with a BMI < 40 kg.m^-2 , in whom an ED₉₀ of 0.35 IU (95%CI 0.15-0.52 IU) has previously been demonstrated.

A new non-invasive procedure for refractory PPH after vaginal delivery and caesarean section

Worldwide, the incidence of postpartum haemorrhage (PPH) is ∼6% and it is the leading cause of maternal mortality. The present study introduces a non-invasive procedure called bilateral cervix apex clamping (BCAC) as a new treatment for refractory PPH. A total of 13 vaginal deliveries and 5 caesarean section patients received the BCAC procedure to stop bleeding. During the procedure, the anterior and posterior walls of the cervical apex were clamped using toothless ovum forceps from the left and right side. The procedure was terminated when the bleeding had nearly stopped without clamping. The success rate of the procedure was 94.4% (17/18) overall, and 92.3% for vaginal delivery and 100% in caesarean section patients. Only one case of vaginal delivery did we resort to exploratory laparotomy and hysterectomy as amniotic fluid embolism occurred. The time spent on the procedure was 2-4 min for vaginal delivery cases and 5-7 min for caesarean section patients. The blood loss reduced significantly after the procedure, before the BCAC and after it was 875(450) ml versus 100(80)ml (p < .0001). There was a reduction in the need for UAE (uterine artery embolisation) from 13 in 22,817 deliveries (2013-2015) to 0 in 18,212 deliveries (2016-2017 (p < .001). But no change in the rate of hysterectomy (5/22817 versus 5/18212) (p = .76). BCAC is a simple, easy, safe, effective and non-invasive procedure that can decrease bleeding in patients with PPH.Impact statementWhat is already known on this subject? The BCAC clamping procedure was first described in Russia 80 years ago as the Genkel-Tikanadze method. But a PUBMED search did not identify and previous studies published on use of the technique.What do the results of this study add? The results of this study show that the BCAC clamping procedure can reduce bleeding significantly in refractory postpartum haemorrhage, when the uterine body is well contracted. The procedure can be performed after both in vaginal delivery and caesarean section. It can also reduce the necessity for UAE and balloon tamponade.What are the implications of these findings for clinical practice and/or further research? BCAC can be used after the failure of regular first line therapy for postpartum haemorrhage.

Differential effects of different delivery methods on progression to severe postpartum hemorrhage between Chinese nulliparous and multiparous women: a retrospective cohort study

BACKGROUND

Delivery methods are associated with postpartum hemorrhage (PPH) both in nulliparous and multiparous women. However, few studies have examined the difference in this association between nulliparous and multiparous women. This study aimed to explore the difference of maternal and neonatal characteristics and delivery methods between Chinese nulliparous and multiparous women, and then examine the differential effects of different delivery methods on PPH between these two-type women.

METHODS

Totally 151,333 medical records of women who gave birth between April 2013 to May 2016 were obtained from the electronic health records (EHR) in a northern province, China. The severity of PPH was estimated and classified into blood loss at the level of < 900 ml, 900-1500 ml, 1500-2100 ml, and > 2100 ml. Neonatal and maternal characteristics related to PPH were derived from the same database. Multiple ordinal logistic regression was used to estimate associations.

RESULTS

Medical comorbidities, placenta previa and accreta were higher in the nulliparous group and the episiotomy rate was higher in the multiparous group. Compared with spontaneous vaginal delivery (SVD), the adjusted odds (aOR) for progression to severe PPH due to the forceps-assisted delivery was much higher in multiparous women (aOR: 9.32; 95% CI: 3.66-23.71) than in nulliparous women (aOR: 1.70; 95% CI: 0.91-3.18). The (aOR) for progression to severe PPH due to cesarean section (CS) compared to SVD was twice as high in the multiparous women (aOR: 4.32; 95% CI: 3.03-6.14) as in the nulliparous women (aOR: 2.04; 95% CI: 1.40-2.97). However, the (aOR) for progression to severe PPH due to episiotomy compared to SVD between multiparous (aOR: 1.24; 95% CI: 0.96-1.62) and nulliparous women (aOR: 1.55; 95% CI: 0.92-2.60) was not significantly different. The (aOR) for progression to severe PPH due to vacuum-assisted delivery compared to SVD in multiparous women (aOR: 2.41; 95% CI: 0.36-16.29) was not significantly different from the nulliparous women (aOR: 1.05; 95% CI: 0.40-2.73).

CONCLUSIONS

Forceps-assisted delivery and CS methods were found to increase the risk of severity of the PPH. The adverse effects were even greater for multiparous women. Episiotomy and the vacuum-assisted delivery, and SVD were similar to the risk of progression to severe PPH in either nulliparous or multiparous women. Our findings have implications for the obstetric decision on the choice of delivery methods, maternal and neonatal health care, and obstetric quality control.

Accuracy of postpartum hemorrhage coding in the Swedish Pregnancy Register

INTRODUCTION

Postpartum hemorrhage (PPH) is recognized as a leading cause of obstetric morbidity and mortality. Population-wide studies have used International Classification of Diseases (ICD) diagnostic codes to track and report the prevalence of PPH. Although the 10th revision (ICD-10) was introduced in Sweden in 1997, the accuracy of ICD-10 codes for PPH is not known. Thus, the aim was to determine the accuracy of diagnostic coding for PPH in the Swedish Pregnancy Register.

MATERIAL AND METHODS

We performed a retrospective cohort study of 609 807 deliveries in Sweden between 2014 and 2019. Information on ICD-10 codes for PPH and estimated blood loss were extracted from the Swedish Pregnancy Register. Using an estimated blood loss >1000 mL as the reference standard, we evaluated the diagnostic accuracy of ICD-10 codes for PPH by estimating sensitivity, specificity, positive predictive value and negative predictive value with exact binomial 95% confidence intervals (CIs). In our secondary analysis, we assessed the ICD-10 coding accuracy for severe PPH, defined as an estimated blood loss >1000 mL and transfusion of at least 1 unit of red blood cells registered in the Scandinavian Donations and Transfusion database.

RESULTS

Of the 609 807 deliveries, 43 312 (7.1%) had an ICD-10 code for PPH and 45 071 (7.4%) had an estimated blood loss >1000 mL. The ICD codes had a sensitivity of 88.5% (95% CI 88.2-88.7), specificity of 99.4% (95% CI 99.4-99.4), positive predictive value of 92.0% (95% CI 91.8-92.3) and negative predictive value of 99.1% (95% CI 99.1-99.1). In our secondary analysis, on deliveries with severe PPH, the sensitivity for an ICD code was 91.3% (95% CI 90.7-91.9), whereas specificity was 83.5% (95% CI 82.3-84.6).

CONCLUSIONS

Our findings indicate that ICD-10 codes for PPH in Sweden have moderately high sensitivity and excellent specificity. These results suggest that PPH diagnostic codes in medical records and linked pregnancy and birth registers can be used for research, quality improvement and reporting PPH prevalence in Sweden.

Evaluation of Risk-Assessment Tools for Severe Postpartum Hemorrhage in Women Undergoing Cesarean Delivery

OBJECTIVE

To examine and compare the validity of three known risk-assessment tools (CMQCC [California Maternal Quality Care Collaborative], AWHONN [Association of Women's Health, Obstetric and Neonatal Nurses], and NYSBOH [New York Safety Bundle for Obstetric Hemorrhage]) in women undergoing cesarean delivery.

METHODS

We conducted a retrospective cohort study that evaluated all women undergoing cesarean delivery at 23 weeks of gestation or longer from 2012 to 2017 at an urban hospital with average of 1,200 cesarean deliveries per year. Data were obtained by chart review. Severe postpartum hemorrhage was defined as transfusion of at least four units of packed red blood cells during the intrapartum or postpartum period. For each risk-assessment tool, women were stratified into low-risk, medium-risk, and high-risk groups. Risk factors were examined using multivariable logistic regression.

RESULTS

Of 6,301 women who underwent cesarean delivery, a total of 76 (1.2%) had severe postpartum hemorrhage. Women classified as low- or medium-risk had lower rates of severe postpartum hemorrhage (0.4-0.6%) compared with women classified as high-risk (1.8-5.1%) (P<.001). Risk factors that were included in all three tools that were associated with severe postpartum hemorrhage included placenta accreta, placenta previa or low-lying placenta, placental abruption, hematocrit less than 30%, and prior uterine scar. Factors included in only one or two tools that were associated with severe postpartum hemorrhage included having more than four previous vaginal deliveries (CMQCC and AWHONN), stillbirth (AWHONN), and more than four prior births (NYSBOH). Area under the curve and 95% CI for CMQCC, AWHONN, and NYSBOH were all moderate-CMQCC 0.77 (0.71-0.84), AWHONN 0.69 (0.65-0.74), and NYSBOH 0.73 (0.67-0.79), respectively (AWHONN being most sensitive [88% with high-risk as cut-off] and CMQCC being most specific [87% with high-risk as cut-off]).

CONCLUSIONS

Risk-assessment tools had moderate prediction to identify high-risk groups at risk for severe postpartum hemorrhage after cesarean delivery.

Bilateral cervix apex clamping procedure can be used as a new noninvasive second line therapy for postpartum hemorrhage

In this study, we present a noninvasive procedure of bilateral cervix apex clamping (BCAC) procedure to control refractory postpartum hemorrhage (PPH) in vaginal delivery as a new second line therapy for refractory PPH. The procedure clamps the anterior and posterior walls of the cervical apex using toothless ovum forceps to arrest bleedingafter the failure of the first line therapy for PPH. 44 women were performed BCAC to control persistent bleeding in 13,359 vaginal deliveries from 1 January 2016 to 31 May 2018. In all of the BCAC, it can reduce bleeding significantly. The bleeding speed after BCAC was far less than that before it (2.64 ± 4.99 ml/min vs 20.23 ± 9.40 ml/min P < 0.001). The blood loss after BCAC was less than that before it (146.57 ± 170.83 vs 797.84 ± 200.73 ml P < 0.001). 41 (93.2%) BCACsucceeded and 3(6.8%) failed turned to intrauterine balloon tamponade, 2 succeeded and 1 failed turned to hysterectomy. In the successful group the bleeding speed after the BCAC was 1.38 ± 0.99 ml/min less than that 19.84 ± 6.27 ml/min in the failure group. (p < 0.001). The blood loss in the success group is also less than that in the failure ones after BCAC (107.29 ± 78.36mL vs 683.33 ± 202.07 ml P < 0.001) Even in the failure group, the bleeding speed also reduced after BCAC compared with that before BCAC (19.84 ± 6.27 vs 29.17 ± 7.12 ml/min p = 0.02). But the blood loss had no statistical difference (683.33 ± 202.07 vs 950 ± 132.29 ml p = 0.27) In all of the 13,359 vaginal deliveries, the incidence of PPH was 1.21% while the severe PPH was only 0.27%. The BCAC may reduce the incidence of severe PPH (0.27%) and also can reduce the necessity of IUBT (3/13,359 0.22‰), uterine artery embolization (UAE) (0/13,359) and even the exploratory laparotomy hysterectomy (1/13,359). Because it is effective, convenient, cheap and noninvasive, so we think it can be used as a new second line noninvasive treatment for PPH.

Effect of Maternal Body Mass Index on Postpartum Hemorrhage

BACKGROUND

It is unclear whether obesity is a risk factor for postpartum hemorrhage. The authors hypothesized that obese women are at greater risk of hemorrhage than women with a normal body mass index.

METHODS

The authors conducted a cohort study of women who underwent delivery hospitalization in California between 2008 and 2012. Using multilevel regression, the authors examined the relationships between body mass index with hemorrhage (primary outcome), atonic hemorrhage, and severe hemorrhage (secondary outcomes). Stratified analyses were performed according to delivery mode.

RESULTS

The absolute event rate for hemorrhage was 60,604/2,176,673 (2.8%). In this cohort, 4% of women were underweight, 49.1% of women were normal body mass index, 25.9% of women were overweight, and 12.7%, 5.2%, and 3.1% of women were in obesity class I, II, and III, respectively. Compared to normal body mass index women, the odds of hemorrhage and atonic hemorrhage were modestly increased for overweight women (hemorrhage: adjusted odds ratio [aOR], 1.06; 99% CI, 1.04 to 1.08; atonic hemorrhage: aOR, 1.07; 99% CI, 1.05 to 1.09) and obesity class I (hemorrhage: aOR, 1.08; 99% CI, 1.05 to 1.11; atonic hemorrhage; aOR, 1.11; 99% CI, 1.08 to 1.15). After vaginal delivery, overweight and obese women had up to 19% increased odds of hemorrhage or atonic hemorrhage; whereas, after cesarean delivery, women in any obesity class had up to 14% decreased odds of severe hemorrhage.

CONCLUSIONS

The authors' findings suggest that, at most, maternal obesity has a modest effect on hemorrhage risk. The direction of the association between hemorrhage and body mass index may differ by delivery mode.

Severe Maternal Morbidity in Canada: Temporal Trends and Regional Variations, 2003-2016

OBJECTIVE

This study sought to quantify temporal trends and provincial and territorial variations in severe maternal morbidity (SMM) in Canada.

METHODS

The study used data on all hospital deliveries in Canada (excluding Québec) from 2003 to 2016 to examine temporal trends and from 2012 to 2016 to study regional variations. SMM was identified using diagnosis and intervention codes. Contrasts among periods and regions were quantified using rate ratios (RRs) and 95% confidence intervals (CIs). Temporal changes were also assessed using chi-square tests for trend (Canadian Task Force Classification II-1).

RESULTS

The study population included 3 882 790 deliveries between 2003 and 2016 and 1 418 545 deliveries between 2012 and 2016. Severe hemorrhage rates increased from 44.8 in 2003 to 62.4 per 10 000 deliveries in 2012 (P for trend <0.0001) and then declined to 41.8 per 10 000 deliveries in 2016 (P for trend <0.0001). Maternal intensive care unit admission and sepsis rates decreased between 2003 and 2016, whereas rates of stroke, severe uterine rupture, hysterectomy, obstetric embolism, shock, and assisted ventilation increased. Rates of composite SMM in 2012-2016 were higher in Newfoundland and Labrador (RR 1.15; 95% CI 1.04-1.26), Nova Scotia (RR 1.11; 95% CI 1.03-1.19), New Brunswick (RR1.22; 95% CI 1.13-1.32), Manitoba (RR 1.09; 95% CI 1.03-1.15), Saskatchewan (RR 1.15; 95% CI 1.09-1.22), the Yukon (RR 1.74; 95% CI 1.35-2.25), and Nunavut (RR 1.76; 95% CI 1.46-2.11) compared with the rest of Canada, whereas rates were lower in Alberta and British Columbia.

CONCLUSION

This surveillance report helps inform clinical practice and public health policy for improving maternal health in Canada.

The safety and effectiveness of Bakri balloon in the management of postpartum hemorrhage: a systematic review

Background: Postpartum hemorrhage (PPH) is a direct cause of maternal death all over the world. A Bakri balloon is recommended by American College of Obstetricians and Gynecologists (ACOG) and World Health Organization (WHO) as a treatment line for PPH unresponsive to uterotonics. We carried out a systematic review to assess the safety and effectiveness of Bakri balloon in the management of PPH.Methods: We searched PubMed, SCOPUS, central Cochrane, and Web of Science, from 2001 to 2018 for randomized controlled trials (RCTs) and observational studies to assess the safety and effectiveness of Bakri balloon on refractory PPH.Results: Twenty-eight articles were included for analysis. The primary indication for the use of a Bakri balloon tamponade was PPH. Only 67.9% (19/28) quantified the estimate blood loss necessary to use the balloon. Uterine atony was the underlying cause of PPH in 75% (21/28) of studies. Most of the studies on Bakri balloon are followed by vaginal birth (3/4). Bakri balloon displacement from the uterine cavity was reported by five publications, with the overall rate being 9% (95% CI: 5-15%). Hysterectomy was necessary for 1% (95% CI: 0-8%) of the women who required the balloon.Conclusions: Bakri balloon seems to be a less effective tool for management of PPH either after vaginal or cesarean delivery.

Maternal outcomes following massive obstetric haemorrhage in an inner-city maternity unit

This retrospective study evaluates the effects of a massive postpartum haemorrhage (PPH) on maternal outcomes in an inner-city London hospital. One hundred and eighty-four cases of a massive primary PPH (>2000 mL) were identified over a seven-year period. A sub-group analysis was performed to assess whether 2000-3000 mL blood loss (134 cases) was associated with specific maternal characteristics or reduced adverse outcomes compared with >3000 mL blood loss (50 cases). Bakri balloon tamponade (BBT) was the most frequent form of surgical management in both groups (21 vs. 46%), followed by compression sutures (16.4 vs. 24%), the 'uterine sandwich' technique (6.7 vs. 14%) and the hysterectomy (0 vs. 4%). There were significant differences between these groups in placenta praevia as the cause of blood loss (8 vs. 22%, p = .01), length of stay (4.6 vs. 5.9 d, p = .02), use of BBT (p = <.01) and hysterectomy (p = .03). PPH is associated with premature maternal morbidity and mortality. The incidence is increasing in high income countries despite various guidelines, skills training and identification of risk factors. A prediction and assessment of blood loss remain the very cornerstone for a prompt, effective management. Our study shows that the morbidity is clearly related to the amount of blood loss and highlights the existing variable practices for the management of PPH. Impact statement What is already known on this subject? A postpartum haemorrhage (PPH) remains a common cause of maternal morbidity and mortality. Massive PPH (>2000 mL) rates continue to rise in developed countries. The management of PPH includes the medical treatment followed by surgical methods including the Bakri balloon tamponade (BBT), compression sutures or a hysterectomy. What do the results of this study add? This retrospective study evaluates the effects of a massive PPH (blood loss >2000 mL) on maternal outcomes. One hundred and eighty-four cases of a massive PPH were identified over a seven-year period. Sub-group analysis was performed to assess whether a 2000-3000 mL blood loss was associated with specific maternal characteristics and differences in obstetric practice compared with a >3000 mL blood loss. There were significant differences between these groups in placenta praevia, as the cause of blood loss, the length of stay, the use of BBT and the hysterectomy rates. What are the implications of these findings for clinical practice and/or further research? An early identification of the risk factors of a massive PPH is essential to improve maternal outcomes and is an important part of the antenatal, intrapartum and postpartum period. The prediction and assessment of blood loss remain key for a prompt, effective management. The amount of blood loss is related to adverse maternal outcomes and the management techniques applied. BBT has an essential role to play and should be included as part of the core training in the management of a PPH.

Peripartum Haemorrhage, Diagnosis and Therapy. Guideline of the DGGG, OEGGG and SGGG (S2k Level, AWMF Registry No. 015/063, March 2016)

Purpose

This is an official interdisciplinary guideline, published and coordinated by the German Society of Gynaecology and Obstetrics (DGGG), the Austrian Society of Gynaecology and Obstetrics (OEGGG) and the Swiss Society of Gynaecology and Obstetrics (SGGG). The guideline was developed for use in German-speaking countries and is backed by the German Society of Anaesthesiology and Intensive Medicine (DGAI), the Society of Thrombosis and Haemostasis Research (GTH) and the German Association of Midwives. The aim is to provide a consensus-based overview of the diagnosis and management of peripartum bleeding obtained from an evaluation of the relevant literature.

Methods

This S2k guideline was developed from the structured consensus of representative members of the various professional associations and professions commissioned by the Guideline Commission of the DGGG.

Recommendations

The guideline encompasses recommendations on definitions, risk stratification, prevention and management.

Emergency obstetric hysterectomy for life-threatening postpartum hemorrhage: A 12-year review

The aim of the study was to review the operative experiences of emergency hysterectomy for life-threatening postpartum hemorrhage (PPH) performed over a 12-year period at Fujian Provincial Maternity and Children's Hospital; to examine the incidence and risk factors for emergency obstetric hysterectomy; and to evaluate the curative effectiveness and safety of subtotal hysterectomy for life-threatening PPH.The records of all cases of emergency obstetric hysterectomy performed at Fujian Maternity and Children Health Hospital between January 2004 and June 2016 were analyzed. The incidence, risk factors, and outcomes of hysterectomy, the peripartum complications, and the coagulation function indices were evaluated.A total of 152,023 of women were delivered. The incidence of emergency postpartum hysterectomy was 0.63 per 1000 deliveries: 96 patients underwent hysterectomy for uncontrolled PPH, 19 (0.207‰) underwent hysterectomy following vaginal delivery, and 77 (1.28‰) underwent the procedure following cesarean delivery (P < .001). Common risk factors included postpartum prothrombin activity ≤ 50% (61.5%), placenta accreta (43.76%), uterine atony (37.5%), uterine rupture (17.5%), and grand multiparity > 6 (32.3%). Forty-one patients underwent subtotal abdominal hysterectomy (STH) and 55 patients underwent total abdominal hysterectomy (TH). The mean operation time was significantly shorter for TH (193.59 ± 83.41 minutes) than for STH (142.86 ± 78.32 minutes; P = .002). The mean blood loss was significantly greater for TH (6832 ± 787 mL) than for STH (6329 ± 893 mL; P = .003). The mean number of red cell units transfusion was higher during TH (16.24 ± 9.48 units vs 12.43 ± 7.2, respectively; P = .047). Postoperative prothrombin activity was significantly higher than preoperative levels (56.84 ± 14.74 vs 44.39 ± 15.69, respectively; P < .001) in women who underwent TH and in those who underwent STH (57.63 ± 15.68 vs 47.87 ± 12.86, respectively; P < .001). There was no significant difference in the maternal complications after TH or STH for PPH.Cesarean deliveries were associated with an increased risk of emergency hysterectomy, and postpartum prothrombin activity < 50% was the greatest risk factor for hysterectomy in most women who underwent hysterectomy. STH was the preferred procedure for emergency obstetric hysterectomy.

Placental Growth Factor as a Prognostic Tool in Women With Hypertensive Disorders of Pregnancy: A Systematic Review

Supplemental Digital Content is available in the text.

The PlGF (placental growth factor) has been largely demonstrated to be associated with the diagnosis of the hypertensive disorders of pregnancy (HDPs); however, it is unclear how useful it is for the prognosis of the condition. Our objective was to provide a summary of important findings of its prognostic ability by systematically reviewing studies that examined the ability of the PlGF, either independently or combined with other factors, to predict maternal and fetal complications resulting from the HDPs. We included studies published before January 30, 2017, reporting on the use of the PlGF as a prognostic test for women with confirmed HDPs or suspected preeclampsia. Of the 220 abstracts identified through MEDLINE, Embase, and CINAHL (Cumulative Index to Nursing and Allied Health Literature), 17 studies were eligible for our review. Prognostic performance was evaluated by sensitivity, specificity, likelihood ratios, and area under the receiver operating characteristic curve. PlGF showed moderate-to-high evidence (likelihood ratios of ≥5 or ≤0.2 or area under the receiver operating characteristic curves ≥0.70) for identifying women at the highest risk of preterm delivery or neonatal outcomes (10/12 studies) but showed no clinically useful performance for the prediction of adverse maternal outcomes. PlGF may aid in the management of women with HDPs to avert fetal complications. Future studies should determine an optimum threshold for the marker to guide delivery and should examine whether its use for predicting adverse maternal outcomes in women with HDPs can be improved.

Protocol for a pilot, randomised, double-blinded, placebo-controlled trial of prophylactic use of tranexamic acid for preventing postpartum haemorrhage (TAPPH-1)

INTRODUCTION

Postpartum haemorrhage (PPH) is the leading cause of maternal morbidity and mortality worldwide. Despite the availability of multiple uterotonic agents, the incidence of PPH continues to rise. Tranexamic acid (TXA) has been shown to be a safe, effective and inexpensive therapeutic option for the treatment of PPH, however, its use prophylactically in mitigating the risk of PPH is unknown. This pragmatic randomised prospective trial assesses the feasibility and safety of administering TXA at the time of delivery for the prevention of PPH.

METHODS AND ANALYSIS

A pilot pragmatic randomised double-blinded placebo-controlled trial will be performed. 58 singleton parturients at term >32 weeks, undergoing either spontaneous vaginal delivery, or caesarean section will be randomised to receive 1 g of TXA or placebo (0.9% saline) intravenously. The primary outcome assessed will be the feasibility of administrating TXA, along with collecting data regarding safety of drug administration. The groups will also be analysed on efficacy of mitigating the onset of PPH and clinically relevant variables. Demographic, feasibility, safety and clinical endpoints will be summarised and the appropriate measures of central tendency and dispersion will be presented.

ETHICS AND DISSEMINATION

This protocol was approved by the Sunnybrook Health Sciences Centre Research Ethics Board (number: 418-2016). The results will be disseminated in a peer-reviewed journal and at scientific meetings.

TRIAL REGISTRATION NUMBER

NCT03069859; Pre-results.

Risk Factors for Severe Postpartum Hemorrhage After Cesarean Delivery: Case-Control Studies

BACKGROUND

Women who undergo intrapartum caesarean delivery (CD) are at increased risk of postpartum hemorrhage (PPH) compared with those undergoing prelabor CD. To determine whether the presence and strength of the associations between individual risk factors and severe PPH vary among women undergoing prelabor CD or intrapartum CD, stratified analyses are needed according to CD subtype.

METHODS

To identify risk factors for severe PPH within 2 distinct CD populations, prelabor CD and intrapartum CD, we performed 2 case-control studies. Women in each study cohort delivered at a tertiary obstetric center in the United States between 2002 and 2012. For each study, cases were women who had a blood loss ≥1500 mL or who received an intraoperative or postoperative transfusion up to 48 hours after delivery. Risk factors for severe PPH among women undergoing prelabor CD or intrapartum CD were examined in separate logistic regression models.

RESULTS

For prelabor CD, we identified 269 cases and 550 controls. Clinical factors with the highest adjusted odds for severe PPH during prelabor CD were general anesthesia (adjusted odds ratio [aOR] = 22.3; 95% confidence interval [CI], 4.9-99.9; reference group = spinal anesthesia), multiple pregnancies (aOR = 8.0; 95% CI, 4.2-15.0; reference group = singleton pregnancy), and placenta previa (aOR = 6.3; 95% CI, 3.4-11.8). For intrapartum CD, we identified 278 cases and 572 controls. Clinical factors with the highest adjusted odds for severe PPH during intrapartum CD were general anesthesia (aOR = 5.4; 95% CI, 1.7-17.1), multiple pregnancies (aOR = 3.2; 95% CI, 1.7-6.3), and a predelivery hemoglobin ≤ 9.9 g/dL (aOR = 3.0; 95% CI, 1.3-6.9; reference group = predelivery hemoglobin ≥ 11 g/dL).

CONCLUSIONS

Women who undergo prelabor CD and intrapartum CD have several shared risk factors for severe PPH (general anesthesia and multiple pregnancies). However, the risk factor profiles for severe PPH differed between these CD cohorts. Recognizing these differences may be important when planning resources and interventions for high-risk patients undergoing either prelabor or intrapartum CD.

Maternal, Labor, Delivery, and Perinatal Outcomes Associated with Placental Abruption: A Systematic Review

Objective Risk factors for placental abruption have changed, but there has not been an updated systematic review investigating outcomes. Methods We searched PubMed, EMBASE, Web of Science, SCOPUS, and CINAHL for publications from January 1, 2005 through December 31, 2016. We reviewed English-language publications reporting estimated incidence and/or risk factors for maternal, labor, delivery, and perinatal outcomes associated with abruption. We excluded case studies, conference abstracts, and studies that lacked a referent/comparison group or did not clearly characterize placental abruption. Results A total of 123 studies were included. Abruption was associated with elevated risk of cesarean delivery, postpartum hemorrhage and transfusion, preterm birth, intrauterine growth restriction or low birth weight, perinatal mortality, and cerebral palsy. Additional maternal outcomes included relaparotomy, hysterectomy, sepsis, amniotic fluid embolism, venous thromboembolism, acute kidney injury, and maternal intensive care unit admission. Additional perinatal outcomes included acidosis, encephalopathy, severe respiratory disorders, necrotizing enterocolitis, acute kidney injury, need for resuscitation, chronic lung disease, infant death, and epilepsy. Conclusion Few studies examined outcomes beyond the initial birth period, but there is evidence that both mother and child are at risk of additional adverse outcomes. There was also considerable variation in, or absence of, the reporting of abruption definitions.

Risks and trends of red blood cell transfusion in obstetric patients: a retrospective study of 45,213 deliveries using administrative data

BACKGROUND

Transfusion data for obstetric patients are scarce. Identifying characteristics associated with red blood cell transfusion (RBCT) is of importance to better identify patients who would benefit from blood conservation strategies as the risk of alloimmunization from RBCT has the potential to affect the fetus and newborn.

STUDY DESIGN AND METHODS

We conducted a retrospective cohort study using hospital administrative data to identify trends and risk factors of RBCT in obstetric patients. Data were analyzed according to the mode of delivery.

RESULTS

A total of 45,213 deliveries were captured between January 1, 2007, and December 31, 2013. A higher proportion of patients undergoing cesarean sections (C/Ss) received an RBCT (2.3%) compared to other modes of delivery (0.7% for spontaneous vaginal delivery, 1.5% for instrumental delivery; p < 0.001). In addition, the risk of RBCT increased over the 7-year period for those patients undergoing C/S (relative risk [RR], 1.56; 95% confidence interval [CI], 1.14-2.15). An unavailable hemoglobin (Hb) level (RR, 12.94; 95% CI, 7.39-22.66) and Hb level of 70 to 80 g/L (RR, 7.78; 95% CI = 5.21-11.60) were strongly associated with RBCT among women undergoing C/S. Earlier gestational age at induction increased the risk of RBCT across all modes of delivery.

CONCLUSIONS

The higher frequency of RBCT for unknown and low Hb supports the need for predelivery patient blood management at the time of delivery. The additional risk factors associated with RBCT identified may be used to develop risk stratification tools by mode of delivery to assist in the identification of patients at the highest risk of requiring RBCT.

The association between the time from oxytocin cessation during labour to Cesarean delivery and postpartum blood loss: a retrospective cohort study

PURPOSE

Prolonged exposure to oxytocin during augmentation of labour is associated with uterine atony and an increased risk of postpartum hemorrhage (PPH) due to oxytocin receptor desensitization. Cessation of oxytocin infusion during labour may facilitate recovery of oxytocin receptor function, which then helps to restore myometrial contractility and decrease postpartum blood loss. We examined the association between oxytocin recovery interval, i.e., the time from discontinuing oxytocin to Cesarean delivery (CD) for labour arrest, and blood loss.

METHODS

This retrospective cohort study included women who underwent CD for labour arrest following oxytocin-augmented labour from July 1, 2013 to July 19, 2015 at our institution. Data were collected on patient demographics, labour and delivery characteristics, oxytocin induction and augmentation, recovery interval, and PPH risk factors. The primary outcome was estimated blood loss (EBL), calculated using the hematocrit variation method.

RESULTS

Data on 490 women were analyzed. The mean (standard deviation) EBL was 1,341 (577) mL; the amount of oxytocin administered during labour was 6,447 (6,868) mU, and the oxytocin recovery interval was 99 (65) min. Every ten-minute increase in the recovery interval was associated with a 10-mL decrease in EBL (95% confidence interval [CI], -18 to -3; P = 0.009). Morbidly obese women had a significantly higher EBL than those with a body mass index < 40 kg·m^-2 (mean difference, 572 mL; 95% CI, 382 to 762; P < 0.001). The amount and duration of oxytocin administered during labour, but not the oxytocin recovery interval, was associated with the use of additional interventions to control PPH (P = 0.005).

CONCLUSION

Our study shows that an increase in the oxytocin recovery interval is associated with a decrease in blood loss at CD in women with oxytocin augmented labour. These data support discontinuing the oxytocin infusion as soon as the decision is made to proceed with CD for labour arrest, particularly in morbidly obese women.