Methods for blood loss estimation after vaginal birth.

BACKGROUND: Almost 358,000 women die each year in childbirth, mainly in low-income countries. More than half of all maternal deaths occur within 24 hours of giving birth; severe bleeding in the postpartum period is the single most important cause. Depending on the rate of blood loss and other factors, such as pre-existing anaemia, untreated postpartum haemorrhage (PPH) can lead to hypovolaemic shock, multi-organ dysfunction, and maternal death, within two to six hours.This review investigated different methods for estimating blood loss. The most common method of measuring blood loss during the third stage of labour is visual estimation, during which the birth attendant makes a quantitative or semi-quantitative estimate of the amount of blood lost. In direct blood collection, all blood lost during the third stage of labour (except for the placenta and membranes) is contained in a disposable, funnelled, plastic collector bag, which is attached to a plastic sheet, and placed under the woman's buttocks. When the bleeding stops, there are two options: the bag can be weighed (also called gravimetric technique), or the bag can be calibrated, allowing for a direct measurement. A more precise measurement of blood loss is haemoglobin concentration (Hb) in venous blood sampling and spectrophotometry. With the dye dilution technique, a known quantity of dye is injected into the vein and its plasmatic concentration is monitored after the uterus stops bleeding. Using nuclear medicine, a radioactive tracer is injected, and its concentration is monitored after the uterus stops bleeding. Although hypothetically, these advanced methods could provide a better quantification of blood loss, they are difficult to perform and are not accessible in most settings. OBJECTIVES: To evaluate the effect of alternative methods to estimate blood loss during the third stage of labour, to help healthcare providers reduce the adverse consequences of postpartum haemorrhage after vaginal birth. SEARCH METHODS: We searched Cochrane Pregnancy and Childbirth's Trials Register (2 February 2018), ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP; 21 March 2018), and reference lists of retrieved studies. SELECTION CRITERIA: All randomised trials, including cluster-randomised trials, evaluating methods for estimating blood loss after vaginal birth. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trials for inclusion and risk of bias, extracted data, and checked them for accuracy. MAIN RESULTS: The search retrieved 62 reports in total. Of these, we assessed 12 reports in full, corresponding to six trials. We included three trials and excluded one; two trials are ongoing.The included trials were conducted in hospital settings. Two trials were conducted in India; the third trial was a large cluster-randomised trial, which took place in 13 European countries. Overall, we judged the included trials to be at a low risk of bias. One study evaluated the use of calibrated drapes versus visual estimation, another evaluated the use of calibrated drapes versus the gravimetric technique (weight of blood-soaked materials), therefore, we were unable to pool the data from the two studies. The third study did not measure any of the outcomes of interest, so did not contribute data to the analyses.Direct measurement using calibrated drapes versus visual estimationOne cluster-randomised controlled trial in 13 western European countries, with over 25,000 women, examined this comparison.The trial did not report on postpartum anaemia (defined as Hb lower than 9 mg/dL), blood loss greater than 500 mL, or maternal infection.Moderate-quality evidence suggests there is probably little or no difference between groups in: severe morbidity (coagulopathy, organ failure, intensive care unit admission; adjusted risk ratio (RR) 0.82, 95% confidence interval (CI) 0.48 to 1.39); the risk of blood transfusion (adjusted RR 0.82, 95% CI 0.46 to 1.46); the use of plasma expanders (adjusted RR 0.77, 95% CI 0.42 to 1.42); and the use of therapeutic uterotonics (adjusted RR 0.87, 95% CI 0.42 to 1.76).Direct measurement using calibrated drapes (Excellent BRASSS-V Drape™) versus gravimetric techniqueOne randomised controlled trial in India, with 900 women, examined this comparison.The trial did not report on postpartum anaemia (defined as Hb lower than 9 mg/dL), severe morbidity, or maternal infection.High-quality evidence showed that using calibrated drapes improved the detection of blood loss greater than 500 mL when compared with the gravimetric technique (RR 1.86, 95% CI 1.11 to 3.11). Low-quality evidence suggests there may be little or no difference in the risk of blood transfusion between the two groups (RR 1.00, 95% CI 0.06 to 15.94), or in the use of plasma expanders, reported as intravenous fluids given for PPH treatment (RR 0.67; 95% CI 0.19 to 2.35). High-quality evidence showed little or no difference in the use of therapeutic uterotonics (RR 1.01, 95% CI 0.90 to 1.13), but the use of therapeutic uterotonics was extremely high in both arms of the study (57% and 56%). AUTHORS' CONCLUSIONS: Overall, the evidence in this review is insufficient to support the use of one method over another for blood loss estimation after vaginal birth. In general, the quality of evidence for our predefined outcomes ranged from low to high quality, with downgrading decisions due to imprecision. The included trials did not report on many of our primary and secondary outcomes.In trials that evaluate methods for estimating blood loss during vaginal birth, we believe it is important to measure their impact on clinical maternal and neonatal outcomes, along with their diagnostic accuracy. This body of knowledge needs further, well designed, appropriately powered, randomised controlled trials that correlate blood loss with relevant clinical outcomes, such as those listed in this review.

Identifying the risk: a prospective cohort study examining postpartum haemorrhage in a regional Australian health service.

BACKGROUND: In industrialised countries the incidence of postpartum haemorrhage (PPH) is increasing, for which exact etiology is not well understood. Studies have relied upon retrospective data with estimated blood loss as the primary outcome, known to be underestimated by clinicians. This study aimed to explore variables associated with PPH in a cohort of women birthing vaginally in coastal Queensland, Australia, using the gravimetric method to measure blood loss. METHODS: Women were prospectively recruited to participate using an opt-out consent process. Maternal demographics; pregnancy history; model of care; mode of birth; third stage management practices; antenatal, intrapartum and immediate postpartum complications; gravimetric and estimated blood loss; and haematological laboratory data, were collected via a pre-designed data collection instrument. Descriptive statistics were used for demographic, intrapartum and birthing practices. A General Linear Model was used for multivariate analysis to examine relationship between gravimetric blood loss and demographic, birthing practices and intrapartum variables. The primary outcome was a postpartum haemorrhage (blood loss > 500 ml). RESULTS: 522 singleton births were included in the analysis. Maternal mean age was 29 years; 58% were multiparous. Most participants received active (291, 55.7%) or modified active management of third stage (191, 36.6%). Of 451 births with valid gravimetric blood loss recorded, 35% (n = 159) recorded a loss of 500 ml or more and 111 (70%) of these were recorded as PPH. Gravimetric blood loss was strongly correlated with estimated blood loss (r = 0.88; p < 0.001). On average, the estimated blood loss was lower than the gravimetric blood loss, about 78% of the measured value. High neonatal weight, perineal injury, complications during labour, separation of mother and baby, and observation of a gush of blood were associated with PPH. Nulliparity, labour induction and augmentation, syntocinon use were not associated with PPH. CONCLUSIONS: In contrast to previous study findings, nulliparity, labour induction and augmentation were not associated with PPH. Estimation of blood loss was relatively accurate in comparison to gravimetric assessment; raising questions about routine gravimetric assessment of blood loss following uncomplicated births. Further research is required to investigate type and speed of blood loss associated with PPH.

Pictorial estimation of blood loss in a birthing pool--an aide memoire.

The aim of this article is to share some photographic images to help midwives visually estimate blood loss at water births. PubMed, CINAHL and MEDLINE databases were searched for relevant research. There is little evidence to inform the practice of visually estimating blood loss in water, as discussed further on in the article. This article outlines a simulation where varying amounts of blood were poured into a birthing pool, captured by photo images. Photo images of key amounts like 150mls, 300mls and 450mls can be useful visual markers when estimating blood loss at water births. The speed of spread across the pool may be a significant factor in assessing blood loss. The author recommends that midwives and educators embark on similar simulations to inform their skill in estimating blood loss at water births.

Comparison of active and expectant management on the duration of the third stage of labour and the amount of blood loss during the third and fourth stages of labour: a randomised controlled trial.

BACKGROUND: Postpartum haemorrhage is one of the most important causes of maternal death. OBJECTIVES: To evaluate the effect of active management of the third stage of labour on the amount of blood loss in the third and fourth stages of labour, and the duration of the third stage of labour. METHODS: A randomised controlled trial was completed on 200 women who gave birth at a maternity unit in Iran. In the intervention group (n=100), 10IU of oxytocin was injected intramuscularly into the mother following birth of the anterior shoulder of the baby. After clamping and cutting the umbilical cord, the uterus was pushed upwards and posterior, while the cord was pulled down with constant and intermittent traction until the placenta was delivered. In the control group (n=100), on observing signs of placental separation, the placenta was expulsed by maternal force. In both groups of women, blood loss was measured at birth using collecting devices, and drapes and sheets were weighed to estimate blood loss. FINDINGS: Mean blood loss during the third stage of labour was 216.93+/-165.16 ml and 232.12+/-150.35 ml in the intervention and control groups, respectively; the difference was not significant (p=0.49). In contrast, mean blood loss during the fourth stage of labour differed significantly (422.62+/-324.7 ml and 327.27+/-255.99 ml in the intervention and control groups, respectively; p=0.02). The mean duration of the third stage of labour was less in the intervention group than in the control group (4.69+/-5.51 mins and 6.34+/-5.03 mins; p=0.028). CONCLUSIONS: Active management did not decrease blood loss during the third stage of labour, but did decrease the duration of this stage. Active management was associated with increased blood loss during the fourth stage of labour. Due to conflicting results between studies, further research should be undertaken to determine the optimal method by which to manage the third stage of labour.

Arterial cord blood lactate at birth correlates with duration of pushing efforts.

OBJECTIVE: To evaluate the impact of the duration of pushing efforts on arterial cord blood lactate values. METHODS: This was a prospective observational study of 124 consecutive normal vaginal deliveries in a tertiary teaching hospital. Arterial cord blood lactate was determined immediately at birth with a test strip method. Univariate and multivariate analyses were performed to check for clinical determinants of lactate levels. The main measure was lactate according to the duration of pushing efforts. RESULTS: Arterial cord lactates increased significantly and were strongly correlated with the duration of pushing efforts, independent of gestational age and birthweight. Women pushing for more than 20 min had higher arterial cord blood lactates (4.9 +/- 1.4 vs. 3.3 +/- 1.16 mM, respectively) and a higher rate of lactates >6 mM (18 vs. 3%) than those pushing for less than 20 min. CONCLUSION: At normal delivery, arterial cord blood lactates increase significantly with the duration of pushing efforts. Pushing for more than 20 min is associated with an increased risk of metabolic acidosis in the neonate. Further studies are required to evaluate the clinical significance of these observations.

Cost-effectiveness analysis of active management of third-stage labour in Vietnam.

Active management of the third stage of labour (AMTSL) using oxytocin substantially reduces postpartum haemorrhage (PPH), a leading cause of maternal mortality. An economic analysis of the use of AMTSL was conducted as part of an intervention study in Thanh Hoa Province, Vietnam. A spreadsheet was used to calculate various scenarios and estimate the costs and outcomes of the routine use of AMTSL with oxytocin in Uniject compared with oxytocin in ampoules, and AMTSL compared with no AMTSL. We estimated the health outcomes from probabilities that were generated from the effectiveness portion of the AMTSL intervention project. The study also estimates the costs of treating PPH and the net incremental costs of AMTSL (costs and savings); examines the impact of different scenarios of PPH rate and Uniject cost; and estimates the potential cost per PPH case and PPH death averted. The additional net cost per woman of providing AMTSL with ampoules was just US dollar 0.20 in the base case; using Uniject devices added only US dollar 0.08 more per woman to the ampoule cost. Varying the rate of PPH had the biggest effect; if the underlying PPH rate were 8%, the incremental cost of AMTSL drops to just US dollar 0.07 per woman with ampoules and the cost to avert a case of PPH is US dollar 2.10 with ampoules and US dollar 4.52 with Uniject. The low net incremental cost of AMTSL suggests that the introduction of AMTSL in primary-level facilities in Vietnam can reduce the incidence of PPH and benefit women's health without adding much to national health care costs.

The importance of delayed cord clamping for Aboriginal babies: a life-enhancing advantage.

Third stage management has typically focused on women and postpartum haemorrhage. Clamping and cutting the umbilical cord following the birth of the baby has continued to be a routine part of this focus. Active versus physiological management of third stage is generally accepted as an evidence-based plan for women to avoid excessive blood loss. Other considerations around this decision are rarely considered, including the baby's perspective. This paper provides a review of the literature regarding timing of clamping and cutting of the umbilical cord and related issues, and discusses the consequences for babies and in particular *Aboriginal babies. Iron stores in babies are improved (among other important advantages) if the cord is left to stop pulsating for 3 min before being clamped. Such a simple measure of patience and informed practice can make a long lasting difference to a baby's health and for Aboriginal babies this advantage can be critical in the short and the long term for their development and wellbeing. To achieve much needed reductions in infancy anaemia and essential increases in infant survival, delayed cord clamping and cutting is recommended for all Aboriginal babies.

Association between anaemia during pregnancy and blood loss at and after delivery among women with vaginal births in Pemba Island, Zanzibar, Tanzania.

The study sought to identify determinants of blood loss at childbirth and 24 hours postpartum. The study was nested in a community-based randomized trial of treatments for anaemia during pregnancy in Wete Town, Pemba Island, Zanzibar, United Republic of Tanzania. Status of anaemia during pregnancy, nutritional information, obstetric history, and socioeconomic status were assessed at enrollment during routine antenatal care. Pregnant women presented for spontaneous vaginal delivery, and nurse-midwives collected information on labour and delivery via partograph. Blood-stained sanitary napkins and pads from childbirth and 24 hours postpartum were quantified using the alkaline hematin method. Moderate-to-severe anaemia (Hb <90 g/L) at enrollment was strongly associated with blood loss at delivery and the immediate postpartum period, after adjusting for maternal covariates and variables of biological relevance to blood loss. Greater blood loss was associated (p<0.10) with duration of the first stage of labour, placental weight, receipt of oxytocin, preterm birth, and grand multiparity. The findings provide unique evidence of a previously-suspected link between maternal anaemia and greater blood loss at childbirth and postpartum. Further research is needed to confirm these findings on a larger sample of women to determine whether women with moderate-to-severe anaemia are more likely to experience postpartum haemorrhage and whether appropriate antenatal or peripartum care can affect the relationships described here.

Follistatin serum concentrations during full-term labour in women--significant differences between spontaneous and induced labour.

Follistatin has been isolated from human placenta and has been identified in human foetal membranes and fluids. Serum follistatin levels in women rise during pregnancy particularly near term. In this study, we examined the effect of induction and stage of labour on maternal plasma concentrations of follistatin. Women who gave birth after a normal pregnancy were retrospectively divided into three groups: those who went in labour spontaneously (n = 33), needed induction by amniotomy and IV oxytocin (n = 18) or underwent planned caesarean section (n = 10). Serum was collected at 38-40 weeks of gestation, periodically through labour with a vaginal examination and once within 36 h postpartum and assayed for oestradiol, progesterone, prolactin and C-reactive protein. Follistatin was measured using a rabbit antiserum (#204) raised against purified 35 kDa bovine follistatin. Human recombinant follistatin was used as both standard and tracer. Concentrations of follistatin at 38-40 weeks of gestation were significantly different between groups. Those who had a spontaneous labour had concentrations higher than those who were induced. Similarly, those who were induced had concentrations higher than those who underwent a caesarean. In the spontaneous group, follistatin rose during labour, peaking at 57.9 +/- 5.48 ng/ml at > 3 cm of cervical dilation, and after delivery follistatin decreased to 26.16 +/- 3.4 ng/ml at 24 h post-delivery. In induced patients follistatin continued increasing to peak following delivery at 26.9 +/- 3.0 ng/ml and decreased at > 3 h post-delivery. Follistatin concentrations in caesarean section patients at 24 h post-surgery (18.53 +/- 3.74 ng/ml) were not different from that before the surgery and were comparable with the other two groups. Follistatin is clearly implicated in the onset of labour; however, further studies with a larger cohort of women are necessary to determine the nature of its role.

Estimating blood loss after birth: using simulated clinical examples.

AIM: To determine the accuracy of the estimation of blood loss using simulated clinical examples. SETTING: Over 100 attendees came together at a seminar about postpartum haemorrhage in June 2006. Five blood loss assessment stations were constructed, each containing a simulated clinical example. Each station was numbered and was made up of a variety of equipment used in birthing suites. Over 5L of 'artificial' blood was made. The artificial blood was similar to the colour and consistency of real blood. SAMPLE: A convenience sample of 88 participants was given a response sheet and asked to estimate blood loss at each station. Participants included midwives, student midwives and an obstetrician. RESULTS: Blood in a container (bedpan, kidney dish) was more accurately estimated than blood on sanitary pads, sheets or clothing. Lower volumes of blood were also estimated correctly by more participants than the higher volumes. DISCUSSION: Improvements are still needed in visual estimation of blood loss following childbirth. Education programs may increase the level of accuracy. CONCLUSION: We encourage other clinicians and educators to embark upon a similar exercise to assist midwives and others to improve their visual estimation of blood loss after birth. Accurate estimations can ensure that women who experience significant blood loss can receive appropriate care and the published rates of postpartum haemorrhage are correct.

Measurement of blood loss at childbirth and postpartum.

OBJECTIVE: To accurately measure blood loss during childbirth in a developing country. METHOD: The alkaline hematin technique was used to quantify blood lost during delivery and 24 h postpartum in 158 women in Pemba Island, Zanzibar. RESULT: Women were found to lose less blood during childbirth and 24 h postpartum than previously reported. Compared with laboratory values, nurse-midwives approximated blood loss accurately (mean difference, i.e., mean underestimation by nurse-midwives, 4.90 mL); however, their imprecision was greater for higher laboratory values. CONCLUSION: This study may prompt further investigation, as no comparable data exist for developing countries where maternal mortality is high and severe anemia prevalent.

Fear, pain and stress hormones during childbirth.

AIMS: To investigate the course of fear, pain and stress hormones during labor, and the associations between fear, pain, stress hormones and duration of labor in nulliparous women with and without epidural analgesia (EDA). METHOD: One day during gestation weeks 37-39, urinary and salivary samples were collected to measure catecholamines and cortisol. Hourly during labor, the participants answered the Delivery Fear Scale and a pain intensity scale, and urinary and salivary samples were collected to measure stress hormones. RESULTS: The course of fear, pain and stress hormones differed throughout labor in women with and without EDA. Pain and cortisol increased throughout labor in women without EDA. Women who received EDA had more fear, but not more pain, before the administration of the EDA than women who did not receive EDA. Pain, fear and catecholamines decreased when women received EDA, but fear and pain increased again later in labor. Fear and pain correlated, as well as levels of fear in the different phases of labor. During phase one of labor epinephrine and duration of the phase were negatively correlated. CONCLUSION: The course of fear, pain and concentrations of stress hormones differed, highly influenced by the administration of EDA. Fear and pain correlated more pronounced than stress hormones and fear, pain and duration of labor.

[Evaluation of glucose and cholesterol levels in the mother and newborn infant in the perinatal period]. / Ocena poziomu glukozy i cholesterolu u matki i noworodka w okresie okoloporodowym.

In 30 live born newborns the connections were assessed between glucose and cholesterol levels in umbilical cord blood after birth, and also in maternal blood before and two days after birth. Statistically significant differences of glucose and cholesterol levels were found between mothers and newborns in the perinatal period. Attention is called to greater independence of cholesterol (total, free and esterified) levels in newborn and mother in perinatal period.

Maternal serum cortisol and prolactin variations during labor.

Maternal serum cortisol (F) and prolactin (PRL) levels were measured during labor in 20 uncomplicated pregnancies. Four pregnant women were admitted with ruptured membranes (RM group) and 16 were admitted with intact membranes (IM group), ten with spontaneous onset of labor (SL group) and 10 with induced labor (IL group), five with a prolonged for duration labor (PL group) and 15 with a normal for duration labor (NL group). Before the inset of labor F levels were statistically higher (p less than 0.05) in the RM group (x = 975 ng/ml), than in the IM group (x = 664 ng/ml), and also in the SL group (x = 783 ng/ml), than in the IL group (x = 679 ng/ml). During labor, in all twenty pregnant women a marked rise of F (from x = 726 ng/ml before the onset of labor, to x = 911 ng/ml) and a marked fall of PRL (from x = 161 ng/ml to x = 122 ng/ml) were observed (p less than 0.05). In the PL group the F elevation and the PRL drop were more pronounced (p less than 0.001). After placental separation, PRL levels increased slightly while F values remained unchanged. These changes in hormone levels before and during labor could be attributed to the emotional and physical stress of labor.

[Eutopic parturition: psychoprophylaxis or extradural analgesia. Influence on the endocrine response]. / Parto eutócico: psicoprofilaxis o analgesia extradural. Influencia sobre la respuesta endocrina.

Prolactin, ACTH, cortisol and HGH levels have been studied on 30 pregnant women in three different periods: during the labour, at the delivery and 24 hours later. They were divided into 3 groups depending on the analgesia: I) no analgesia (n = 10); II) psychoprophylaxis (n = 10), and III) extradural analgesia (n = 10). Prolactin levels increased during delivery and 24 hours later. A significant increase of ACTH levels (p less than 0.01) was observed during the delivery in the 3 groups even though they were under hasal values 24 hours later. Cortisol increased 38% (p less than 0.01) and 52% (p less than 0.02) in II and III groups, respectively during the delivery. No difference was found with HGH. Our results suggest that endocrine response modified by labour and delivery doesn't change with different analgesia techniques.