Prenatal anaemia and risk of postpartum haemorrhage: a cohort analysis of data from the Predict-PPH study.

BACKGROUND: Most previous clinical studies investigating the connection between prenatal anaemia and postpartum haemorrhage (PPH) have reported conflicting results. OBJECTIVES: We examined the association between maternal prenatal anaemia and the risk of PPH in a large cohort of healthy pregnant women in five health institutions in Lagos, Southwest Nigeria. METHODS: This was a prospective cohort analysis of data from the Predict-PPH study that was conducted between January and June 2023. The study enrolled n = 1222 healthy pregnant women giving birth in five hospitals in Lagos, Nigeria. The study outcome, WHO-defined PPH, is postpartum blood loss of at least 500 milliliters. We used a multivariable logistic regression model with a backward stepwise conditional approach to examine the association between prenatal anaemia of increasing severity and PPH while adjusting for confounding factors. RESULTS: Of the 1222 women recruited to the Predict-PPH study between January and June 2023, 1189 (97·3%) had complete outcome data. Up to 570 (46.6%) of the enrolled women had prenatal anaemia while 442 (37.2%) of those with complete follow-up data had WHO-defined PPH. After controlling for potential confounding factors, maternal prenatal anaemia was independently associated with PPH (adjusted odds ratio = 1.37, 95% confidence interval: 1.05-1.79). However, on the elimination of interaction effects of coexisting uterine fibroids and mode of delivery on this association, a sensitivity analysis yielded a lack of significant association between prenatal anaemia and PPH (adjusted odds ratio = 1.27, 95% confidence interval: 0.99-1.64). We also recorded no statistically significant difference in the median postpartum blood loss in women across the different categories of anaemia (P = 0.131). CONCLUSION: Our study revealed that prenatal anaemia was not significantly associated with PPH. These findings challenge the previously held belief of a suspected link between maternal anaemia and PPH. This unique evidence contrary to most previous studies suggests that other factors beyond prenatal anaemia may contribute more significantly to the occurrence of PPH. This highlights the importance of comprehensive assessment and consideration of various maternal health factors in predicting and preventing this life-threatening obstetric complication.

Incidence and Antepartum Risk Factors of Severe Postpartum Haemorrhage in Anaemic Pregnant Women in Lagos, Nigeria: A Secondary Cohort Analysis.

BACKGROUND: The magnitude and risk factors for postpartum haemorrhage (PPH) have been extensively investigated, although little is currently known about the incidence and predictors of severe PPH, specifically among women affected by prenatal anaemia in Nigeria. OBJECTIVES: The study determined the incidence and antepartum risk factors of severe PPH in anaemic pregnant women in five health institutions in Lagos, Southwest Nigeria. METHODS: A secondary analysis was performed using the data of pregnant women with anaemia from the "Predict-PPH" study that was conducted between January and June 2023. This study included n=570 pregnant women affected by anaemia who gave birth in five hospitals in the Lagos metropolis of Nigeria. The study outcome was severe PPH, defined as an estimated blood loss of at least 1000 mL within 24 hours of childbirth. A backward stepwise conditional approach in a multivariable logistic regression model was utilised to identify the independent risk factors for severe PPH in anaemic pregnant women. RESULTS: Of the 570 women with prenatal anaemia enrolled in the primary study, 42 (7.4%) had severe PPH. The identified independent risk factors for severe PPH were maternal obesity (adjusted OR = 3.85, 95% CI = 1.85-8.02), antepartum haemorrhage in index pregnancy (adjusted OR = 2.98, 95% CI = 1.29-6.90), uterine fibroids (adjusted OR = 6.10, 95% CI = 2.39-15.52), delivery gestational age ≥39 weeks (adjusted OR = 2.62, 95% CI = 1.23-5.56), and delivery by caesarean birth (adjusted OR = 16.75, 95% CI = 5.81-48.31). CONCLUSION: About one in 13 anaemic pregnant women enrolled in the study developed severe PPH during childbirth. Maternal obesity, antepartum bleeding in the current pregnancy, co-existing uterine fibroids in pregnancy, delivery gestational age beyond 38 weeks, and caesarean birth in the current pregnancy were factors that were significantly associated with severe PPH in anaemic pregnant women. These findings underscore the importance of increased vigilance during both the antenatal and peripartum periods to identify women with these risk factors for the initiation of timely interventions to prevent severe PPH.

Prevalence and determinants of moderate-to-severe anaemia in the third trimester of pregnancy: a multicenter cross-sectional study in Lagos, Nigeria.

The high burden of anaemia during pregnancy underscores the urgent need to gain a comprehensive understanding of the factors contributing to its widespread occurrence. Our study assessed the prevalence and the trends of moderate-to-severe anaemia (MSA) in late pregnancy (28 to 36 weeks) and then investigated the key determinants driving this prevalence among women in Lagos, Nigeria. We conducted a secondary data analysis involving 1216 women enrolled in the Predict-PPH study between January and March 2023. We employed a multivariate binary logistic regression model with a backward stepwise selection approach to identify significant predictors of MSA. The study revealed a 14.5% prevalence of MSA during pregnancy. Independent predictors of MSA included having given birth to two or more children (adjusted odds ratio = 1.46, 95% confidence interval: 1.03-2.07), having a maternal body mass index (BMI) of 28 kg/m2 or higher (adjusted odds ratio = 1.84, 95% confidence interval: 1.29-2.61), having less than tertiary education (adjusted odds ratio = 1.51, 95% confidence interval: 1.08-2.11), and being unemployed (adjusted odds ratio = 1.97, 95% confidence interval: 1.19-3.26). It is crucial for pregnant women, particularly those with higher parities and elevated BMI, to be monitored regularly for anaemia and its consequences during their antenatal care. Additionally, addressing the link between low education, unemployment, and anaemia necessitates comprehensive strategies that empower women in terms of education and economic status to enhance the overall well-being of individuals and communities, ultimately reducing the prevalence of anaemia and associated health issues in pregnancy.