Reduced maternal selenium levels in pregnant and lactating Nigerian women: should routine selenium supplementation be advocated?

BACKGROUND

Deficiencies in micronutrients are common in our environment, leading to indiscriminate replacement strategies. Selenium is an antioxidant micronutrient that may undergo depletion during pregnancy and lactation. Regrettably, information in this matter is scanty in Nigeria.

OBJECTIVES

To determine maternal selenium concentration during pregnancy and lactation.

METHODS

This was a cross-sectional research involving 120 pregnant women, 40 in each trimester. They were attending antenatal clinic of one tertiary and two secondary health care facilities in Enugu, Southeastern Nigeria. Control subjects constitute age, parity and socioeconomic matched 35 apparently healthy, non pregnant women. Serum selenium concentration was measured during pregnancy and postpartum. Breast milk selenium concentration was also determined by Atomic Absorption Spectrophotometer (AAS).

RESULTS

The mean serum selenium levels were significantly decreased (P < 0.0001) in pregnancy when compared with non-pregnant control subjects; also as pregnancy progressed. However, there was a non significant increase immediately after birth. In the breast milk, selenium concentration significantly decreased (P < 0.0001) as lactation progressed.

CONCLUSION

The observed significant decreases in the levels of selenium during pregnancy and breast milk may leave the mothers and their neonates at risk and, therefore, may necessitate maternal supplementation. Dietary intervention such as food diversification and bio-fortification is recommended to improve dietary selenium intakes in pregnant and lactating mothers, and infants in this region.