The Effect of Maternal Haemoglobinopathies and Iron Deficiency Anaemia on Foetal Growth Restriction: A Systematic Review and Meta-Analysis

Maternal anaemia is a significant global health issue that adversely affects both maternal and foetal outcomes, particularly, intrauterine growth restriction (IUGR). This systematic review and meta-analysis aimed to consolidate existing evidence on the impact of maternal anaemia on the risk of IUGR. We conducted a comprehensive search across PubMed, Embase, Cochrane and Web of Science until 28 February 2024. Eligible studies included observational designs that reported maternal anaemia and its association with IUGR or small for gestational age (SGA) outcomes. The pooled odds ratios (ORs) were calculated using a random-effects model and heterogeneity was assessed with the I² statistic. The R software (version 4.3) was used for statistical analyses. A total of 38 studies involving 3,871,849 anaemic and 27,978,450 non-anaemic pregnant women were included. The pooled analysis demonstrated that anaemia in pregnancy is associated with a significantly increased risk of IUGR (OR = 1.30, 95% CI: 1.05–1.62, I² = 97%). Subgroup analyses by anaemia severity showed non-significant associations for mild (OR = 0.84, 95% CI: 0.58–1.23) and moderate anaemia (OR = 0.98, 95% CI: 0.48–1.98), while severe anaemia indicated a higher, though non-significant, risk of IUGR (OR = 1.42, 95% CI: 0.69–2.93). Maternal anaemia is associated with a heightened risk of IUGR, highlighting the critical need for effective management and early intervention strategies within prenatal care settings. Future research should focus on elucidating the effects of different severities of anaemia on birth outcomes, including IUGR and long-term effects later in life.