Maternal haemoglobin level at booking visit and its effect on adverse pregnancy outcome

To determine the effect of maternal haemoglobin levels at booking visit on pregnancy outcome.

A prospective study was carried out at two Medical Officer of Health areas in a district in Sri Lanka, including 817 pregnant mothers who were followed up until delivery. Maternal haemoglobin level was measured according to specified standard protocols. The reliability and the accuracy of haemoglobin measurements were assessed and were found to be satisfactory. Pregnancy outcome was defined in terms of miscarriage, maternal morbidities, preterm birth (PTB), low birth weight (LBW) and small for gestational age (SGA) infants. Potential confounding factors for each pregnancy outcome were also assessed. Multiple logistic regression was applied and the results were expressed as odds ratios (OR) and 95% confidence intervals (95% CI).

The prevalence of anaemia (Hb < 11 g/dL) was 7.1% (95% CI 5.4-8.9%). Anaemia during pregnancy was not significantly associated with any of the pregnancy outcomes studied. Reference range for haemoglobin measurements among mothers with normal pregnancy outcome was 10.4-13.9 g/dL. Haemoglobin level of >13.9 g/dL had a significant adverse association with maternal morbidities (OR 3.0; 95% CI 1.03-8.90) and LBW (OR 3.95; 95% CI 1.30-12.0) compared with the reference range.

Although anaemia during pregnancy was not adversely associated with any of the pregnancy outcomes, Hb level of >13.9 g/dL was adversely associated with maternal morbidities and LBW.