Time to redefine prolonged third stage of labor? A systematic review and meta-analysis of the length of the third stage of labor and adverse maternal outcome after vaginal birth

OBJECTIVE

This study aimed (1) to assess the association between the length of the third stage of labor and adverse maternal outcome after vaginal birth and (2) to evaluate whether earlier manual placenta removal reduces the risk of adverse outcome.

DATA SOURCES

PubMed, MEDLINE, Embase, ClinicalTrials.gov, the Cochrane Library, Journals@Ovid, and the World Health Organization International Clinical Trials Registry were searched from January 1, 2000, to June 13, 2023.

STUDY ELIGIBILITY CRITERIA

All studies that assessed adverse maternal outcome, defined as any maternal complication after vaginal birth, concerning the length of the third stage of labor and the timing of manual placenta removal were included.

METHODS

The included studies were evaluated using the Conducting Systematic Reviews and Meta-Analyses of Observational Studies of Etiology methodology. Pooled odds ratios with 95% confidence intervals were calculated. Heterogeneity (I2 test) was assessed, subgroup analyses were performed, and 95% prediction intervals were calculated.

RESULTS

To meet the first objective, 18 cohort studies were included. The assessed cutoff values for the length of the third stage of labor were 15, 30, and 60 minutes. Women with a third stage of labor of ≥15 minutes had an increased risk of postpartum hemorrhage compared with those with a third stage of labor of <15 minutes (odds ratio, 5.55; 95% confidence interval, 1.74-17.72). For women without risk factors for postpartum hemorrhage, the odds ratio was 2.20 (95% confidence interval, 0.75-6.49). Among women with a third stage of labor of ≥60 minutes vs women with a third stage of labor of <60 minutes, the odds ratio was 3.72 (95% confidence interval, 2.36-5.89). The incidence of red blood cell transfusion was higher for a third stage of labor of ≥30 minutes than for a third stage of labor of <30 minutes (odds ratio, 3.23; 95% confidence interval, 2.26-4.61). Of note, 3 studies assessed the timing of placenta removal and the risk of adverse maternal outcome. However, the results could not be pooled because of the different outcome measures. Moreover, 1 randomized controlled trial (RCT) reported a significantly higher incidence of hemodynamic compromise in women with manual placenta removal at 15 minutes than in women with manual placenta removal at 10 minutes (30/156 [19.2%] vs 10/156 [6.4%], respectively), whereas 2 observational studies reported a lower risk of bleeding among women without manual placenta removal.

CONCLUSION

Although the risk of adverse maternal outcome after vaginal birth increases when the third stage of labor exceeds 15 minutes, there is no convincing supporting evidence that reducing the length of the third stage of labor by earlier manual removal of the placenta can reduce the incidence of adverse maternal outcome.

Retrospective study to assess the effect of epidural analgesia on labor progress and women's pelvic floor muscle from the perspective of electromyography

OBJECTIVE

Epidural analgesia has been widely used as a form of pain relief during labor and its safety has been gradually recognized. However, few studies of the effect of epidural analgesia on the pelvic floor are known. Thus, we aim to analyze the effect of epidural analgesia on labor progress and women's pelvic floor muscle from the perspective of electromyography systematically. In addition, obstetric risk factors for dysfunction of pelvic floor muscle after vaginal delivery were also evaluated.

METHODS

Childbirth data of 124 primiparas who gave first birth vaginally in our hospital and their pelvic floor function assessment results at postpartum 7 weeks were retrospectively collected. Pelvic floor muscle electromyogram screenings were performed by a biofeedback electro-stimulant therapy instrument.

RESULTS

There was no significant difference in the percentage of episiotomy, forceps, artificial rupturing membrane, and the application of oxytocin, except perineal laceration. Woman who implemented epidural analgesia experienced a longer stage of labor. Statistically, there was no significant difference in the total score and pelvic floor muscle strength. The risk factors for the value of the pre-rest phase include the age of pregnant women, the fetal weight, and the length of the second stage while the value of the post-rest phase was only associated with the fetal weight and the length of the second stage. In addition, the value of type I muscles was associated with the gravida and fetal weight while the value of type II muscles was only associated with forceps. The sustained contraction was correlated with the gravida and the total scores had a significant correlation with forceps.

CONCLUSION

Epidural analgesia during labor is approved to be a safe and effective procedure to relieve pain with very low side effects on the mode of labor and pelvic floor muscle. The assessment of pelvic floor muscle before pregnancy is beneficial in guiding the better protection of pelvic floor muscle function. According to the evaluation results, the doctors can control the associated risk factors as much as possible to reduce the injury of pregnancy and parturition to the pelvic floor.

Duration of the Third Stage of Labor and Estimated Blood Loss in Twin Vaginal Deliveries

Objective  The main aim of this study was to characterize the duration of the third stage of labor and estimated blood loss in twin vaginal deliveries. Study Design  This was a retrospective case-control study. The data was collected from deliveries at the University of Arkansas for Medical Sciences in Little Rock, Arkansas, from January 2013 to June 2017. Women were identified who had twin gestation, were delivered vaginally, and whose maternal age was greater than 18 years old. Women were excluded if they had an intrauterine fetal demise, delivered either/both fetuses via cesarean, history of a previous cesarean or a fetus with a congenital anomaly. If a subject met criteria to be included in the study, the next normal singleton vaginal delivery was used as the control subject. Results  There were 132 singleton vaginal deliveries and 133 twin vaginal deliveries analyzed. There was no significant difference in the length of the third stage of labor between twin and singleton vaginal deliveries except in the 95th percentile of the distribution. Mothers delivering twins had an increase in third-stage duration by 7.618 minutes (95% confidence interval [CI]: 0.73, 14.50; p  = 0.03) compared with those who delivered singletons. The twin group had a higher estimated blood loss than singleton deliveries. The increase in blood loss in the twin group was 149.02 mL (95% CI: 100.2, 197.8), 257.01 mL (95% CI: 117.9, 396.1), and 381.53 mL (95% CI: 201.1, 562.1) at the 50th, 90th, and 95th percentiles, respectively. When the third stage of labor was at the 90th percentile or less in twin pregnancy (14 minutes), estimated blood loss was less than 1000 mL. Conclusion  Twin pregnancy is a known risk factor for postpartum hemorrhage. As the duration of the third stage prolongs, the risk for hemorrhage also increases. We recommend delivery of the placenta in twin pregnancies by 15 minutes to reduce this risk. Key Points The third stage is longer in twin pregnancy at extremes.Twin placentas should be delivered by 15 minutes.Manually extract the placenta when third stage is prolonged.

Does epidural analgesia influence labor progress in women aged 35 or more?

Background: During the last decades, the age of pregnant women significantly increased. The incidence of maternal and labor complications is higher among older women, but conclusive data have not been delivered whether labor epidural analgesia (EA) may affect the duration of labor and delivery outcomes in this population of patients. The aim of this study is to evaluate the effect of EA among women aged over 35 years.Methods: We retrospectively reviewed medical records of all, singleton, at term deliveries, laboring with EA, between December 2011 and October 2017. Women aged ≥35 years (study group) were compared with women aged <35 years (control group) to evaluate EA effects on the duration of labor and neonatal outcome.Results: The study enrolled 459 women with EA: 122 women were included in the study group and 337 in the control group. The multiple regression analysis showed that parity was an independent variable for a shorter dilation period (p = .002), second stage length (p = .0001) and for the total labor duration (p = .0001); neonatal weight was significant for a shorter dilation period (p = .005) and for the total labor duration (p = .002); maternal age and cervical dilatation at the beginning of EA did not influence neither the period of the labor stages nor the total labor duration (p > .05).Conclusions: Results of this study indicate that women aged ≥35 with EA may have labor duration and neonatal short-term outcomes similar to younger women with EA.

Risk factors, early and late postpartum complications of retained placenta: A case control study

OBJECTIVES

To identify risk factors and complications associated with 3^rd stage of labor removal of placental fragments (3^rd SRPF) by manual uterine revision under a strict protocol.

STUDY DESIGN

Ten years retrospective register-based cohort study of vaginal deliveries. Women with 3^rd SRPF n = 3297 (exposed) and those without n = 97,888 (non exposed) were compared.

MAIN OUTCOMES MEASURES

(1) risk factors for 3^rd SRPF aOR (95%CI) (2) early (2a) and late (2b) maternal complications.

RESULTS

(1) Risk factors for 3^rd SRPF procedure were assisted reproductive technologies 2.20 (1.73-2.34), preterm delivery 2.53 (2.21-2.88), preeclampsia 1.66 (1.25-2.21) Multiple previous early pregnancy loss (>3) 1.40(1.19-1.66), VBAC 1.26(1.13-1.47) and epidural analgesia 1.56 (1.46-1.69). (2a) Early complications: puerperal fever 1.1% vs 0.3%, blood transfusion 9.0% vs. 0.5%, prolonged maternal hospitalization 21.0% vs. 11.4%, all P < 0.0001. Puerperal readmission was 0.819% in the 3^rd SRPF vs. 0.315% the control group, P < 0.0001. (2b) Late complications: retained placenta and hysteroscopy / D&C rates were significantly higher among the 3^rd SRPF vs. controls: 40.7% vs. 7.1%, 14.8% vs. 3.6% and 48.1% vs. 18.2%, respectively, all P < 0.0001.

CONCLUSION

Uterine revision for 3^rd SPRF is associated with significant early and late maternal morbidity; should be considered discriminative of a population at risk and postpartum health care planning, beyond being a therapeutic intervention.

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.

Does fetal sex affect placental delivery times? A prospective observational study

Objective: The aim of this study was to determine the potential effect of fetal sex on placental delivery times.Study design: This was a prospective observational study of term, singleton, and primiparous pregnant women who underwent vaginal delivery and subsequently delivered a phenotypically normal live infant. Women with labor or pregnancy complications and comorbid diseases were excluded. Women with factors who could lengthen the placental delivery time were also excluded. The cohort was divided into two groups according to fetal sex. A total of 299 vaginal deliveries were included, and placental delivery times were analyzed in both groups.Results: There were 3938 vaginal deliveries during the study period. Of these, 150 male-bearing pregnant women and 149 female-bearing pregnant women who met the inclusion criteria were included in the analysis. The mean placental delivery time was significantly longer in the male-bearing group than the female-bearing group (12.20 versus 8.21 min, p = .01). Birth weight was significantly greater in the male-bearing group than the female-bearing group (3194 versus 3059 g, p = .004). There was no significant between-group difference in maternal age, gestational age, and preconception body mass index (BMI).Conclusion: Fetal sex had a significant effect on the placental delivery time in the present study. Fetal sex should be considered in future clinical trials of placental delivery times.

The Third Stage of Labour in the Extremely Obese Parturient

BACKGROUND

Maternal obesity has been associated with an increased risk for an abnormal progression of labour; however, less is known about the length of the third stage of labour and its relation to maternal obesity.

OBJECTIVE

To determine if the length of the third stage of labour is increased in extremely obese women and its possible correlation with an increased risk for postpartum hemorrhage.

STUDY DESIGN

This was a retrospective cohort study of deliveries from January 2008 to December 2015 at our university hospital. Women with a BMI ≥40 and a vaginal delivery were compared with the next vaginal delivery of a woman with a BMI <30. There were 147 women with a BMI ≥40 compared with 157 with a BMI <30. Outcomes evaluated the length of the third stage of labour and the risk for postpartum hemorrhage and included antepartum, intrapartum, and perinatal complications.

RESULTS

Subjects in the extreme obese group were more likely to be African American, older, diabetic (pregestational and gestational), hypertensive, pre-eclamptic, had a preterm delivery, and underwent an induction of labour. The overall length of the third stage of labour was significantly longer in the extreme obese group, 5 minutes (3, 8 [25th and 75th percentiles]) compared with 4 minutes (3,7) (P = 0.0374) in the non-obese group. Postpartum hemorrhage occurred more often in the extreme obese group (N = 16/147; 11%) compared with the non-obese group (N = 5/157; 3%) (P = 0.01). There were no differences between groups in respect to the following: gravidity, parity, length of the second stage of labour, birth weight, GA at delivery, Apgar score, cord blood gases, hematocrit change, need for postpartum transfusion, operative delivery, and development of chorioamnionitis. After an adjustment for ethnicity, maternal age, diabetes, preeclampsia, preterm labour, hypertension, and induction/augmentation, the analysis failed to show a significant difference in estimated blood loss and postpartum hemorrhage between the groups.

CONCLUSIONS

The length of the third stage of labour is longer in the extreme obese parturient. Postpartum hemorrhage also occurs more often, but after adjustments for confounding variables, it is no longer significant.

A Novel Approach to Detecting Postpartum Hemorrhage Using Contrast-Enhanced Ultrasound

The aim of this study was to estimate the efficacy of contrast-enhanced ultrasound (CEUS) in detecting postpartum hemorrhage (PPH) after cesarean section. This is the first study of CEUS in obstetric hemorrhage. A total of 37 patients, operated at Nagoya University Hospital, underwent CEUS. We evaluated the findings of CEUS, which were qualitatively defined as positive when pooling or leakage of contrast agent was observed in the uterine cavity, by measuring the amount of bleeding during the first 4 h after cesarean section. The time-intensity curve patterns of leaked contrast agents were also analyzed for quantitative prediction of the amount of blood loss. Significant differences between the excessive hemorrhage (N = 7) and non-excessive hemorrhage groups (N = 30) were noted in the occurrence of positive CEUS (p = 0.011). Additionally, mean postpartum blood loss markedly increased in patients with a positive CEUS (p = 0.002). From a quantitative perspective, the time until leakage of contrast agents was detected correlated with the amount of bleeding, but the other characteristics of the time-intensity curve pattern did not provide valuable information. In conclusion, CEUS, which enables bedside assessment and rapid diagnosis, is a promising strategy for the detection of PPH.

Factors contributing to postpartum blood-loss in low-risk mothers through expectant management in Japanese birth centres

OBJECTIVE

To describe aspects of expectant midwifery care for low-risk women conducted in midwifery-managed birth centres during the first two critical hours after delivery and to compare differences between midwifery care, client factors and postpartum blood loss volume.

METHOD

As a secondary analysis from a larger study, this descriptive retrospective study examined data from birth records of 4051 women who birthed from 2001 to 2006 at nine (21%) of the 43 midwifery centres in Tokyo. Nonparametric and parametric analyses identified factors related to increased blood loss. Interviews to establish sequence of midwifery care were conducted.

FINDINGS

The midwifery centres provided care based on expectant management principles from birth to after expulsion of the placenta. Approximately 63.3% of women were within the normal limits of blood loss volume under 500g. A minority of women (12.9%) experienced blood loss between 500 and 800g and 4% had blood loss exceeding 1000g. Blood loss volume tended to increase with infant birth weight and duration of delivery. The total blood loss volume was significantly higher for primiparas than for multiparas during the critical two hours after delivery and for immediately after delivery, yet blood loss volume was significantly higher for multiparas than for primiparas during the first hour after delivery. Preventive uterine massage and umbilical cord clamping after placenta expulsion resulted in statistically significant less blood loss. Identified were two patterns of midwifery care based on expectant management principles from birth to after expulsion of the placenta. The practice of expectant management was not a significant factor for increased postpartum blood loss.

CONCLUSION

These results detail specific midwifery practices and highlight the clinical significance of expectant management with low risk pregnant women experiencing a normal delivery.

Laboratory prediction of primary postpartum haemorrhage: a comparative cohort study

BACKGROUND

Postpartum haemorrhage (PPH) is the leading cause of maternal deaths, the world over. The aim of this study was to determine laboratory parameters that could serve as risk factors for primary PPH.

METHODS

This comparative cohort study involved 350 pregnant women at term who were recruited consecutively from the Komfo Anokye Teaching Hospital, Kumasi, Ghana. PPH was defined as a measured blood loss ≥ 500 ml or enough to cause haemodynamic shock. Basic demographic data was gathered and blood was collected for laboratory assays before delivery. Univariate and multivariate logistic regression models were used to identify variables that were significantly associated with primary PPH.

RESULTS

Of the total recruited study participants (350), five declined to participate and 74 went through caesarean section, episiotomy or instrumental deliveries and were excluded. Of the remaining (271) study participants who went through spontaneous vaginal delivery, fifty five (55) were diagnosed with primary PPH (Group 1) and the remaining 216 were those who did not have PPH (Group 2). Demographic characteristics did not differ between the two groups (P > 0.05). Univariate analysis showed that AST (P = 0.043), urea (P < 0.001), creatinine (P = 0.002), urea-to-creatinine ratio (P = 0.014) and the proportion of abnormal peripheral blood smear (P < 0.001) was higher among women in Group 1 compared to those in Group 2. Women in Group 1 had a significantly lower haemoglobin concentration (10.7 g/dL) compared to those in Group 2 (12.1g/dL). Upon multivariate analysis, an abnormal peripheral blood smear (AOR = 2.9672), Hb, (AOR = 0.5791), moderate to severe anaemia (Hb <10 g/dL) (AOR = 3.1385), Urea (AOR = 3.6435) and intra-renal azotaemia (AOR = 0.1893) remained significant.

CONCLUSION

Many laboratory parameters are associated with primary PPH but only a few are independent risk factors. A total clinical work-up including laboratory evaluation of the independent blood variables identified in this study will help a great deal to identify individuals at high risk for PPH.

The effects of sequential use of oxytocin and sublingual nitroglycerin in the cases of retained placenta

OBJECTIVES

To evaluate the effects of adding sublingual nitroglycerin to oxytocin, for delivery of retained placenta after vaginal delivery.

METHOD

The study was performed as a placebo controlled clinical trial on women who did not finish delivering placenta after 30 min of active management of the third stage of labor. In case group, 1 mg nitroglycerin and in the control group, placebo was prescribed sublingually.

RESULTS

In total, 80 women finished the study. The number of manual removal of placenta did not show significant difference between the two groups [25 women (62.5%) in the case and 30 women (75%) in the control group, p = 0.335]. There was no significant difference between the two groups according to duration of the third stage of labor, hemoglobin index, decline in HB index >30% and maternal vital signs after treatment. There was no significant difference between the two groups according to adverse effects [eight women (20%) in the case group and four (10%) in the control group (p = 0.348)].

CONCLUSION

The sequential use of oxytocin and sublingual nitroglycerin could not lead to delivery of more placentas and did not reduce the necessity of manual removal of placenta in comparison with placebo.

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.

OBJECTIVES

To compare the effectiveness of active versus expectant management of the third stage of labour.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group Trials Register (30 September 2014) 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.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the studies for inclusion, assessed risk of bias and carried out data extraction.

MAIN RESULTS

We included seven studies (involving 8247 women), all undertaken in hospitals, six in high-income countries and one in a low-income country. Four studies compared active versus expectant management, and three compared active versus a mixture of managements. We used random-effects in the analyses because of clinical heterogeneity. There was an absence of high-quality evidence according to GRADE assessments for our primary outcomes. The evidence suggested that for women at mixed levels of risk of bleeding, active management showed a reduction in the average risk of maternal primary haemorrhage at time of birth (more than 1000 mL) (average risk ratio (RR) 0.34, 95% confidence interval (CI) 0.14 to 0.87, three studies, 4636 women, GRADE:very low quality) and of maternal haemoglobin (Hb) less than 9 g/dL following birth (average RR 0.50, 95% CI 0.30 to 0.83, two studies, 1572 women, GRADE:low quality). We also found no difference in the incidence in admission of infants to neonatal units (average RR 0.81, 95% CI 0.60 to 1.11, two studies, 3207 infants, GRADE:low quality) nor in the incidence of infant jaundice requiring treatment (0.96, 95% CI 0.55 to 1.68, two studies, 3142 infants, GRADE:very low quality). There were no data on our other primary outcomes of very severe postpartum haemorrhage (PPH) at the time of birth (more than 2500 mL), maternal mortality, or neonatal polycythaemia needing treatment.Active management also showed a significant decrease in primary blood loss greater than 500 mL, and mean maternal blood loss at birth, maternal blood transfusion and therapeutic uterotonics during the third stage or within the first 24 hours, or both, and significant increases in maternal diastolic blood pressure, vomiting after birth, after-pains, use of analgesia from birth up to discharge from the labour ward and more women returning to hospital with bleeding (outcome not pre-specified). There was also a decrease in the baby's birthweight with active management, reflecting the lower blood volume from interference with placental transfusion.In the subgroup of women at low risk of excessive bleeding, there were similar findings, except there was no significant difference identified between groups for severe haemorrhage or maternal Hb less than 9 g/dL (at 24 to 72 hours).Hypertension and interference with placental transfusion might be avoided by using modifications to the active management package, e.g. omitting ergot and deferring cord clamping, but we have no direct evidence of this here.

AUTHORS' CONCLUSIONS

Although there is a lack of high-quality evidence, active management of the third stage reduced the risk of haemorrhage greater than 1000 mL at the time of birth in a population of women at mixed risk of excessive bleeding, but adverse effects were identified. Women should 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.

Dynamic Changes in the Myometrium during the Third Stage of Labor, Evaluated Using Two-Dimensional Ultrasound, in Women with Normal and Abnormal Third Stage of Labor and in Women with Obstetric Complications

OBJECTIVE

To investigate dynamic changes in myometrial thickness during the third stage of labor.

METHODS

Myometrial thickness was measured using ultrasound at one-minute time intervals during the third stage of labor in the mid-region of the upper and lower uterine segments in 151 patients including: women with a long third stage of labor (n = 30), postpartum hemorrhage (n = 4), preterm delivery (n = 7) and clinical chorioamnionitis (n = 4). Differences between myometrial thickness of the uterine segments and as a function of time were evaluated.

RESULTS

There was a significant linear increase in the mean myometrial thickness of the upper uterine segments, as well as a significant linear decrease in the mean myometrial thickness of the lower uterine segments until the expulsion of the placenta (p < 0.001). The ratio of the measurements of the upper to the lower uterine segments increased significantly as a function of time (p < 0.0001). In women with postpartum hemorrhage, preterm delivery, and clinical chorioamnionitis, an uncoordinated pattern among the uterine segments was observed.

CONCLUSION

A well-coordinated activity between the upper and lower uterine segments is demonstrated in normal placental delivery. In some clinical conditions this pattern is not observed, increasing the time for placental delivery and the risk of postpartum hemorrhage.

Maternal obesity and postpartum haemorrhage after vaginal and caesarean delivery among nulliparous women at term: a retrospective cohort study

Background

Increasing rates of postpartum haemorrhage in developed countries over the past two decades are not explained by corresponding changes in risk factors and conjecture has been raised that maternal obesity may be responsible. Few studies investigating risk factors for PPH have included BMI or investigated PPH risk among nulliparous women. The aim of this study was to determine in a cohort of nulliparous women delivering at term whether overweight and obesity are independent risk factors for major postpartum haemorrhage (PPH ≥1000ml) after vaginal and caesarean section delivery.

Methods

The study population was nulliparous singleton pregnancies delivered at term at National Women’s Hospital, Auckland, New Zealand from 2006 to 2009 (N=11,363). Multivariable logistic regression was adjusted for risk factors for major PPH.

Results

There were 7238 (63.7%) women of normal BMI, 2631 (23.2%) overweight and 1494 (13.1%) obese. Overall, PPH rates were increased in overweight and obese compared with normal-weight women (n=255 [9.7%], n=233 [15.6%]), n=524 [7.2%], p <.001) respectively. There was an approximate twofold increase in risk in obese nulliparous women that was independent of confounders, adjusted odds ratio [aOR (95% CI)] for all deliveries 1.86 (1.51-2.28). Being obese was a risk factor for major PPH following both caesarean 1.73 (1.32-2.28) and vaginal delivery 2.11 (1.54-2.89) and the latter risk was similar after exclusion of women with major perineal trauma and retained placentae. Three additional factors were consistently associated with risk for major PPH regardless of mode of delivery: increasing infant birthweight, antepartum haemorrhage and Asian ethnicity.

Conclusion

Nulliparous obese women have a twofold increase in risk of major PPH compared to women with normal BMI regardless of mode of delivery. Higher rates of PPH among obese women are not attributable to their higher rates of caesarean delivery. Obesity is an important high risk factor for PPH, and the risk following vaginal delivery is emphasised. We recommend in addition to standard practice of active management of third stage of labour, there should be increased vigilance and preparation for PPH management in obese women.

Inability to predict postpartum hemorrhage: insights from Egyptian intervention data

Background

Knowledge on how well we can predict primary postpartum hemorrhage (PPH) can help policy makers and health providers design current delivery protocols and PPH case management. The purpose of this paper is to identify risk factors and determine predictive probabilities of those risk factors for primary PPH among women expecting singleton vaginal deliveries in Egypt.

Methods

From a prospective cohort study, 2510 pregnant women were recruited over a six-month period in Egypt in 2004. PPH was defined as blood loss ≥ 500 ml. Measures of blood loss were made every 20 minutes for the first 4 hours after delivery using a calibrated under the buttocks drape. Using all variables available in the patients' charts, we divided them in ante-partum and intra-partum factors. We employed logistic regression to analyze socio-demographic, medical and past obstetric history, and labor and delivery outcomes as potential PPH risk factors. Post-model predicted probabilities were estimated using the identified risk factors.

Results

We found a total of 93 cases of primary PPH. In multivariate models, ante-partum hemoglobin, history of previous PPH, labor augmentation and prolonged labor were significantly associated with PPH. Post model probability estimates showed that even among women with three or more risk factors, PPH could only be predicted in 10% of the cases.

Conclusions

The predictive probability of ante-partum and intra-partum risk factors for PPH is very low. Prevention of PPH to all women is highly recommended.

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.

OBJECTIVES

To compare the effectiveness of active versus expectant management of the third stage of labour.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group Trials Register (15 February 2011).

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials comparing active versus expectant management of the third stage of labour.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the studies for inclusion, assessed risk of bias and carried out data extraction.

MAIN RESULTS

We included seven studies (involving 8247 women), all undertaken in hospitals, six in high-income countries and one in a low-income country. Four studies compared active versus expectant management, and three compared active versus a mixture of managements. We used random-effects in the analyses because of clinical heterogeneity. There was an absence of high quality evidence for our primary outcomes. The evidence suggested that for women at mixed levels of risk of bleeding, active management showed a reduction in the average risk of maternal primary haemorrhage at time of birth (more than 1000 mL) (average risk ratio (RR) 0.34, 95% confidence interval (CI) 0.14 to 0.87, three studies, 4636 women) and of maternal haemoglobin (Hb) less than 9 g/dL following birth (average RR 0.50, 95% CI 0.30 to 0.83, two studies, 1572 women). We also found no difference in the incidence in admission of infants to neonatal units (average RR 0.81, 95% CI 0.60 to 1.11, two studies, 3207 women) nor in the incidence of infant jaundice requiring treatment (0.96, 95% CI 0.55 to 1.68, two studies, 3142 women). There were no data on our other primary outcomes of very severe postpartum haemorrhage (PPH) at the time of birth (more than 2500 mL), maternal mortality, or neonatal polycythaemia needing treatment.Active management also showed a significant decrease in primary blood loss greater than 500 mL, and mean maternal blood loss at birth, maternal blood transfusion and therapeutic uterotonics during the third stage or within the first 24 hours, or both and significant increases in maternal diastolic blood pressure, vomiting after birth, after-pains, use of analgesia from birth up to discharge from the labour ward and more women returning to hospital with bleeding (outcome not pre-specified). There was also a decrease in the baby's birthweight with active management, reflecting the lower blood volume from interference with placental transfusion.In the subgroup of women at low risk of excessive bleeding, there were similar findings, except there was no significant difference identified between groups for severe haemorrhage or maternal Hb less than 9 g/dL (at 24 to 72 hours).Hypertension and interference with placental transfusion might be avoided by using modifications to the active management package, e.g. omitting ergot and deferring cord clamping, but we have no direct evidence of this here.

AUTHORS' CONCLUSIONS

Although there is a lack of high quality evidence, active management of the third stage reduced the risk of haemorrhage greater than 1000 mL at the time of birth in a population of women at mixed risk of excessive bleeding, but adverse effects were identified. Women should 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.

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.

OBJECTIVES

To compare the effectiveness of active versus expectant management of the third stage of labour.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group Trials Register (May 2010).

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials comparing active versus expectant management of the third stage of labour.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the studies for inclusion, assessed risk of bias and carried out data extraction.

MAIN RESULTS

We included five studies (6486 women), all undertaken in hospitals in high-income countries. Four compared active versus expectant management, and one compared active versus a mixture of managements. Analysis used random-effects because of clinical heterogeneity. Active management reduced the average risk of maternal primary haemorrhage (more than 1000 ml) (risk ratio (RR) 0.34, 95% confidence interval (CI) 0.14 to 0.87, three studies, 4636 women) and of maternal haemoglobin less than 9 g/dl following birth (RR 0.50, 95% CI 0.30 to 0.83, two studies, 1572 women) for women irrespective of their risk of bleeding. We identified no difference in Apgar scores less than seven at five minutes. Active management showed significant increases in maternal diastolic blood pressure, after-pains, use of analgesia and more women returning to hospital with bleeding. There was also a decrease in the baby's birthweight with active management, reflecting the lower blood volume from interference with placental transfusion. There were similar findings for women at low risk of bleeding except there was no significant difference identified for severe haemorrhage. Hypertension and interference with placental transfusion might be avoided by using modifications to the active management package, e.g. omitting ergot and deferring cord clamping, but we have no direct evidence of this here.

AUTHORS' CONCLUSIONS

Active management of third stage reduced the risk of haemorrhage greater than 1000 ml in an unselected population, but adverse effects are identified. Women should be given information on the benefits and harms 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.

Prevalence and risk factors of severe obstetric haemorrhage

OBJECTIVE

To determine the prevalence, causes, risk factors and acute maternal complications of severe obstetric haemorrhage.

DESIGN

Population-based registry study.

POPULATION

All women giving birth (307,415) from 1 January 1999 to 30 April 2004 registered in the Medical Birth Registry of Norway. Information about socio-economic risk factors was obtained from Statistics Norway.

METHODS

Cross-tabulation was used to study prevalence, causes and acute maternal complications of severe obstetric haemorrhage. Associations of severe obstetric haemorrhage with demographic, medical and obstetric risk factors were estimated using multiple logistic regression models.

MAIN OUTCOME MEASURE

Severe obstetric haemorrhage (blood loss of > 1500 ml or blood transfusion).

RESULTS

Severe obstetric haemorrhage was identified in 3501 women (1.1%). Uterine atony, retained placenta and trauma were identified causes in 30, 18 and 13.9% of women, respectively. The demographic factors of a maternal age of > or =30 years and South-East Asian ethnicity were significantly associated with an increased risk of haemorrhage. The risk was lower in women of Middle Eastern ethnicity, more than three and two times higher for emergency caesarean delivery and elective caesarean than for vaginal birth, respectively, and substantially higher for multiple pregnancies, von Willebrand's disease and anaemia (haemoglobin <9 g/dl) during pregnancy. Admissions to an intensive care unit, postpartum sepsis, hysterectomy, acute renal failure and maternal deaths were significantly more common among women with severe haemorrhage.

CONCLUSION

The high prevalence of severe obstetric haemorrhage indicates the need to review labour management procedures. Demographic and medical risk factors can be managed with extra vigilance.