Anaemia in pregnancy is defined by Hb <110g/l at sea level (New 2025).
WHO data is derived from global data. Data drawn from healthy pregnant women in high income countries suggests the range should be 114.6-121.4g/l (Ohuma et al 2020). Data from our local population supports a haemoglobin target >110g/l at 28 weeks. In addition, it is recognized that iron deficiency will be present before anaemia is detectable on a full blood count. This carries a significant symptom burden and is associated with negative outcomes for mother and baby. For these reasons, women with Hb >120g/L at delivery should be considered to have an optimal haemoglobin.
There is no international consensus on this, however studies that have looked at risks and benefits state that a ferritin below 30mcg/L is abnormal and increases the risks detailed above.
Since iron is an essential element in all cells, symptoms of iron deficiency can occur before a fall in haemoglobin. Symptoms and signs are non-specific. Fatigue is the most common symptom; others include weakness, headache, palpitation, dizziness, dyspnoea, poor concentration, hair loss, irritability, depression, and increased frequency of infections.
2.3.2. Dilutional anaemia has long been described as causing physiological anaemia in pregnancy, however it is now thought that iron deficiency is the predominant cause, given correction of anaemia when iron is supplemented in pregnancy.
2.3.3. In the post-partum period, symptoms of iron deficiency include decreased physical performance (tiredness, breathlessness, palpitations), increased risk of infection (urinary tract), impaired lactation, reduced cognitive abilities, emotional instability, and depression (Bergmann et al. 2010). Mother–child interactions are affected as women experience difficulties in caring for their newborn, which compromises the emotional bonds between the mother and baby (Perez et al. 2005).