Article Text

Download PDFPDF
Original research
Pulmonary complications for women with sickle cell disease in pregnancy: systematic review and meta-analysis
  1. Sivarajini Inparaj1,
  2. Mickey Buckingham1,
  3. Laura Oakley2,3,
  4. Paul T Seed4,
  5. Sebastian Lucas5,
  6. Eugene Oteng-Ntim1
  1. 1 Women's and Children’s Health, Guy's and St Thomas' NHS Foundation Trust, London, UK
  2. 2 Non-communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine Faculty of Epidemiology and Population Health, London, UK
  3. 3 Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
  4. 4 Division of Reproduction and Endocrinology, Kings College London, London, UK
  5. 5 Department of Histopathology, KCL School of Medicine, St Thomas’ Hospital, London, United Kingdom
  1. Correspondence to Sivarajini Inparaj, King's College London, London WC2R 2LS, UK; sivarajini.inparaj{at}


Background Sickle cell disease (SCD) is a multisystem disease characterised by vaso-occlusive crisis, chronic anaemia and a shorter lifespan. More patients with SCD are living till reproductive age and contemplating pregnancy. Pulmonary complications in pregnancy are significant causes of maternal morbidity and mortality but yet this has not been systematically quantified. A systematic review and meta-analysis were conducted to quantify the association between SCD and pulmonary complications in pregnancy.

Methods MEDLINE, EMBASE, Web of Science, Cochrane and Maternity and Infant Care databases were searched for publications between January 1998 and April 2019. Observational studies involving at least 30 participants were included. Random-effects models were used for statistical meta-analysis.

Findings Twenty-two studies were included in the systematic review and 18 in the quantitative analysis. The meta-analysis included 3964 pregnancies with SCD and 336 559 controls. Compared with women without SCD, pregnancies complicated by SCD were at increased risk of pulmonary thromboembolism (relative risk (RR) 7.74; 95% CI 4.65 to 12.89). The estimated prevalence of acute chest syndrome and pneumonia was 6.46% (95% CI 4.66% to 8.25%), with no significant difference between the HbSS and HbSC genotypes (RR 1.42; 95% CI 0.90 to 2.23).

Interpretation This meta-analysis highlighted a strong association between SCD and maternal pulmonary complications. Understanding the risks of and the factors associated with pulmonary complications would aid preconceptual counselling and optimal management of the condition in pregnancy, thereby reducing associated maternal morbidity and mortality.

PROSPERO registration number CRD42019124708.

  • pneumonia
  • respiratory infection
  • pulmonary embolism

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


  • Contributors This study was designed, directed and coordinated by EON and as the principal investigator, provided conceptual and technical guidance for all aspects of the project. SI and MB collected, analysed the data. PTS performed the statistical analysis. The manuscript was written by SI and MB and commented on by all authors (LO, SL and EO-N).

  • Funding PTS is partly funded by Tommy’s (Registered charity no. 1060508) and by CLAHRC South London (NIHR) as part of his employment.

  • Competing interests None declared.

  • Patient consent for publication Not required.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data availability statement All data relevant to the study are included in the article or uploaded as supplementary information.

Linked Articles

  • Airwaves
    The Triumvirate