The iron status of rural Nigerian women in the second and third trimesters of pregnancy: implications for the iron endowment and subsequent dietary iron needs of their babies.

Introduction: The aim of the study was to determine the iron status of rural-dwelling pregnant Nigerian women in the second and third trimesters, and to predict their risk of giving birth to babies with suboptimal iron endowment.

Methods: This was a prospective cohort study conducted between April and August 2021. A total of 174 consecutive and consenting pregnant rural dwellers, who met the inclusion criteria, were recruited by convenience sampling from the antenatal clinic of a public hospital in Nsukka, a semirural town in south-east Nigeria. The study participants were aged 21-40 years, and their iron status was determined by measuring blood haemoglobin (Hb) and serum ferritin (SF) concentration. Hb concentration was determined by the cyanmethemoglobin method and the SF concentration was determined by enzyme immunoassay method.

Results: Almost half (47.7%) of the participants had Hb concentrations below 11 g/dL, while about two out of every five (40.8%) had SF concentrations less than 15 µg/L. The prevalence of iron deficiency, iron deficiency anaemia (IDA) and non-iron deficiency anaemia were 40.8%, 23.6% and 24.7%, respectively. The mean SF levels varied with maternal age, gestation stage, pregnancy intervals and the intake of iron supplements. The mean SF concentration was higher in the second trimester than in the third. The mean SF concentration ± standard deviation (37.10±3.02 µg/L) was higher in the group that took iron supplements than in the group that did not (20.76±2.11 µg/L). However, two out of five participants in both groups had SF concentrations less than 15.0 µg/L.

Conclusion: The prevalence of IDA was quite high among the participants in both trimesters even with the widespread intake of the recommended oral iron supplements. About four out of 10 of the participants had SF concentrations of less than 15 µg/L and were thus judged at risk of giving birth to babies with poor iron deposits. Therefore, more effective strategies are needed to monitor and prevent IDA among pregnant women in rural populations of Nigeria and, by inference, other parts of tropical Africa.