Laboratory prediction of primary postpartum haemorrhage: a comparative cohort study

Abstract

BackgroundPostpartum 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.MethodsThis 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.ResultsOf 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.ConclusionMany 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.

Haemoglobin trajectories during pregnancy and associated outcomes using pooled maternity and hospitalization data from two tertiary hospitals

“…A meta‐analysis of cohort studies has also confirmed a significant increase in the risk of preterm birth with anaemia in the first or second trimester . Rates of postpartum haemorrhage did not differ significantly across the trajectory groups in our study, but moderate‐to‐severe anaemia has been associated with blood loss at birth and postpartum haemorrhage in two African studies . High haemoglobin in pregnancy has also been shown to be associated with increased foetal risks, such as stillbirth , perinatal death, preterm delivery and low birthweight .…”

The association between haemoglobin levels in the first 20 weeks of pregnancy and pregnancy outcomes

“…The higher rate of PPH demonstrated in the low compared with normal Hb groups is in line with previous evidence suggesting anaemia is associated with a higher risk of PPH. [24, 25] Women with high antenatal Hb also had a slightly higher PPH rate than those with normal Hb (although not significantly so), but were less likely to be transfused than those with low Hb, which may have been due to better iron reserves or the treating clinicians being more willing to tolerate blood loss before deciding to transfuse. We also found a significantly higher risk of adverse outcomes such as preterm birth, very low birthweight and transfer to higher care or stillbirth for those with high Hb result, as has been found in other studies,[26, 27] possibly due to inadequate plasma volume expansion, or the impaired response to inflammation and infection,[5, 26] or possibly due to high Hb levels before pregnancy.…”

The Optimal Cutoff Level of D-Dimer during Pregnancy to Exclude Deep Vein Thrombosis, and the Association between D-Dimer and Postpartum Hemorrhage in Cesarean Section Patients

“…PPH is a major cause of maternal mortality, along with PTE. Only limited data are available regarding the relationship between the D-dimer level and PPH [13,14]. Whether the D-dimer level is associated with PPH is of interest.…”

“…Though D-dimer cutoff level to exclude symptomatic DVT has been reported, there are few reports on the optimal cutoff level to exclude even asymptomatic DVT to prevent postoperative PTE. In addition, severe postpartum hemorrhage (PPH) is a major cause of maternal death [13]. A few reports are available suggesting that the D-dimer level during pregnancy could be a predictor for PPH [14].…”