A prospective, multicentre, observational, cross-sectional study of the prevalence of blood transfusion associated with caesarean section in KwaZulu-Natal, South Africa

Abstract

Background: Maternal mortality following a caesarean section (CS) is 50-fold higher in Africa compared to high-income countries (HIC), and strongly associated with peripartum haemorrhage. Blood transfusion (BT) may be lifesaving and the identification of associated preoperative factors may improve outcomes, especially in resource-limited settings.
Methods: We conducted a prospective, multicentre cross-sectional study of all consecutive patients undergoing CS at three government-funded hospitals in KwaZulu-Natal. The primary outcome variable was the prevalence of BT. Multivariable binary logistic regression analysis was used to identify factors independently associated with BT. We hypothesised that there would be a higher prevalence of BT, but similar associated factors, compared to in HIC.
Results: We recruited 1 533 patients between January and May 2021. Most patients presented for urgent or emergency CS (72.4%; 1 104/1 524). Human immunodeficiency virus (HIV) infection (38.6%) and hypertensive disorders of pregnancy (23.4%) were the most common comorbidities. In total, 71 patients received a BT, a prevalence of 4.6% (95% confidence interval [CI] 3.6–5.7%). The prevalence of preoperative anaemia was 36.7% (558/1 520; 95% CI 34.3–39.1%), while 6% (92/1 533; 95% CI 4.8–7.2%) of patients had bleeding during or after CS (BDACS). Factors independently associated with BT were ‘major bleeding risk’ (a composite of placenta praevia, abruptio placentae and antepartum haemorrhage) (adjusted odds ratio [aOR] 5.34; 95% CI 2.11–13.52%); preoperative anaemia both mild (2.39; 1.10–5.22%) and moderate/severe (28.37; 12.39–64.97%); platelet count < 100 000 cells/mm³ (5.02; 1.41–17.83%), previous CS (two or more) (2.52; 1.21–5.25%) and BDACS > 1 500 ml (27.86; 6.72–115.54%).
Conclusion: We confirmed that there was a higher prevalence of BT in the hospitals studied than in HIC. Major bleeding risks and BDACS should be identified early to allow appropriate perioperative planning and mobilisation of blood resources. Antenatal anaemia is a preventable and treatable condition. Therefore, earlier diagnosis and treatment should be prioritised. We also showed that even moderate thrombocytopaenia may be associated with BT.