The prevalence, risk factors and outcomes of anaemia in South African pregnant women: a systematic review and meta-analysis

Abstract

BackgroundAnaemia is associated with maternal and perinatal morbidity and mortality. The pooled prevalence of anaemia in the South African (SA) pregnant population was ascertained by systematically reviewing available literature. Severity, risk factors (HIV, tuberculosis, race, province, year of study), maternal morbidity and mortality (hypertensive disorders of pregnancy), birth outcomes (including low birth weight) and supplementation during pregnancy were also described.MethodsEligible studies reported on haemoglobin concentration or prevalence of anaemia in a SA pregnant population and were available in full text. Case-control and estimation studies were excluded with no restriction on the date of publication. PubMed, CINAHL, EMBASE, EBSCO, Ovid maternity and infant care databases, Cochrane Database of Systematic Reviews, Web of Science and SCOPUS were searched, using the keywords ‘anaemia’, ’haemoglobin’, ‘pregnancy’, ‘South Africa’. Risk of bias was conducted using the Hoy tool and the Doi plot and LFK ratio. Overall study quality was assessed using the GRADE tool. Due to heterogeneity amongst studies subgroup analyses were performed (random effects and quality effects model) using MetaXL addon tool for Microsoft Excel.ResultsThe initial search yielded 7010 articles and 26 were selected for inclusion. Twenty studies were cross-sectional, three were longitudinal and one a randomised control trial. Studies ranged in publication year from 1969 to 2020. The pooled prevalence of anaemia in pregnant women in SA was determined to be 31% (95% CI, 23–40%). Hypertensive disorders of pregnancy and low birth weight were associated with anaemia. While iron deficiency was reported as the main cause, other risk factors included HIV and other infections.DiscussionLimitationsThere was limited data reporting on prevalence of anaemia and direct maternal and foetal outcomes. Heterogeneity amongst studies was not explained by subgroup analysis. Majority of cross-sectional study designs reduced the ability to infer causality.InterpretationWhile the prevalence of anaemia remains high and of concern, risk factors are varied. Iron deficiency is still common but the presence of comorbidities also contributes to anaemia and should not be ignored. More longitudinal research into associations between anaemia and birth outcomes is needed due to a lack of available evidence.Systematic review registrationPROSPERO 2020: CRD42020157191.

Prevalence of iron deficiency anemia in pregnancy and its therapeutic response to treatment: a retrospective audit in a tertiary hospital

“…The prevalence here is estimated to be between 46.3 and 60%. 14 From our study and few other studies reported so far in Malaysia highlights that there has not been a change in prevalence over the last two decades. 15 As for ethnicity, our study found that the Indians had a highest prevalence followed by Chinese and Malays.…”

Haemodynamic adjustments in third trimester, among pregnant women undergoing antenatal care at a tertiary hospital in Sokoto, Nigeria

“…6 And although, a recent review paper. 9 attributed low birth weight and hypertensive disease of pregnancy to anaemia, a multicentre and multiethnic study 6 showed no significant relationship between anemia in pregnancy and adverse birth outcome.…”

“…5,6,8 In this regard, even pregnant women taking routine haematenic supplements have been found to have the anemic trend due to varied and disproportionate requirements and hormonal changes. 9,10 Indeed, iron supplementation as traditionally practiced during antenatal services, essentially corrects iron deficiency form of anaemia and may be appropriate only for the malnourished category of pregnant mothers. 9 Therefore, there are far many causes of anemia in pregnancy that iron supplements alone cannot address.…”

“…9,10 Indeed, iron supplementation as traditionally practiced during antenatal services, essentially corrects iron deficiency form of anaemia and may be appropriate only for the malnourished category of pregnant mothers. 9 Therefore, there are far many causes of anemia in pregnancy that iron supplements alone cannot address. 9 However, the last two decades have witnessed improvement in the levels of haemoglobin in women, and of course children.…”

“…9 Therefore, there are far many causes of anemia in pregnancy that iron supplements alone cannot address. 9 However, the last two decades have witnessed improvement in the levels of haemoglobin in women, and of course children.…”