Anaemia in labour is diagnosed when the maternal haemoglobin level falls below established threshold values during the intrapartum period. According to the World Health Organization, a parturient woman is considered anaemic if her haemoglobin level is less than 11.0 g/dL. In the busy setting of Nigerian maternity wards, many women present in active labour with pre-existing, uncorrected nutritional deficiencies compounded by the physiological haemodilution of pregnancy. This condition significantly reduces the blood's oxygen-carrying capacity precisely when both mother and fetus require optimal tissue perfusion to tolerate the physical stress of uterine contractions.
During gestation, maternal blood volume expands by nearly 50%, while red blood cell mass increases by only about 20 to 30%. This disparity creates physiological haemodilution, often termed pseudoanaemia of pregnancy, as plasma volume outpaces erythrocyte production. When iron stores are already depleted before conception, this normal dilutive effect pushes the patient past the safety threshold into true pathological anaemia. Consequently, the cardiovascular system must work harder through increased cardiac output to deliver sufficient oxygen to the uteroplacental unit.
Grading the severity of anaemia guides immediate intrapartum interventions and helps predict the likelihood of postpartum decompensation.
Nutritional iron deficiency remains the leading cause of anaemia among pregnant women in Nigeria, aggravated by diets heavily reliant on phytate-rich cereals with low bioavailability of iron. Malaria endemicity further exacerbates the problem through hemolysis of red blood cells and bone marrow suppression. Parasitic infections like hookworm infestation contribute significantly to chronic gastrointestinal blood loss. Additionally, high parity, short birth intervals, and adolescent pregnancies deplete maternal nutrient reserves before the next labour begins.
An anaemic parturient has a severely diminished physiological reserve, making her highly vulnerable to cardiovascular collapse when faced with normal blood loss during delivery. Uterine atony is more common because an oxygen-starved myometrium fails to contract effectively after the baby is born. For the fetus, chronic intrauterine hypoxia often results in intrauterine growth restriction, low birth weight, and non-reassuring fetal heart traces during the first and second stages of labour.
Detecting anaemia upon admission to the labour ward requires a combination of a quick physical examination and rapid laboratory testing. The nurse inspects the conjunctivae, palmar creases, and nail beds for pallor, though physical signs can be notoriously unreliable in mild cases. The gold standard for confirmation remains the estimation of haemoglobin concentration using a spectrophotometric device or a standard laboratory complete blood count. Fetal wellbeing must be assessed simultaneously through intermittent auscultation or electronic fetal monitoring to rule out ongoing hypoxia.
Intrapartum care for an anaemic woman focuses on conserving her limited energy and optimizing oxygen delivery. The nurse ensures intravenous access is secured immediately upon admission in case rapid volume replacement becomes necessary. Vital signs are monitored more frequently, and the patient is encouraged to adopt a lateral tilt position to prevent aortocaval compression and maintain venous return. Continuous fetal surveillance is maintained to catch early signs of distress, and active management of the third stage of labour is prepared well in advance.
When a woman with severe anaemia experiences excessive bleeding during or after delivery, the situation escalates rapidly into a life-threatening crisis. Active management of the third stage of labour—using prophylactic uterotonics like oxytocin, controlled cord traction, and uterine massage—is mandatory to minimize blood loss. Cross-matched blood must be requested urgently from the blood bank if the haemoglobin is critically low. Midwives must remain vigilant for signs of hypovolemic shock, such as tachycardia, tachypnea, and falling blood pressure, and be prepared to initiate emergency resuscitation protocols.