Iron stores in pregnant Nigerians and their infants at term.

Serum ferritin and blood haemoglobin were evaluated as indices of iron status in 65 pregnant Nigerians and in the cord blood of their full-term infants. All the mothers had taken iron and folate supplementation throughout pregnancy. The mean gravidity was 3.3 +/- 2.0. The mean cord ferritin concentration of 135.9 micrograms/l (77.6-238.2 micrograms/l) was 3.6 times the maternal level of 38.1 micrograms/l (17.3-83.8 micrograms/l). Parity had no effect on the haemoglobin or serum ferritin concentrations of the mothers or those of their babies. Maternal haemoglobin or serum ferritin concentrations correlated significantly (P less than 0.01) with cord levels, in babies with mothers of parity greater than or equal to 5. Infants of mothers with low iron stores (less than 20 micrograms/l) had significantly lower serum ferritin concentrations than infants of iron-replete mothers, which suggests variation in amounts of iron received during intrauterine growth. In order to ensure adequate iron stores in newborn infants, continual use of supplementary oral iron should be encouraged in pregnant Nigerians.