Micro minerals, also known as trace elements, are dietary minerals needed by the human body in very small amounts, yet they are absolutely vital for health and development. While macro minerals like calcium are required in large quantities, micro minerals such as zinc, iodine, and iron act as powerful catalysts and structural components in countless biochemical pathways. For pregnant women in Nigeria, where nutritional deficiencies can pose severe risks, understanding these tiny nutrients helps midwives provide life-saving dietary advice. Iron stands out among all trace elements because the maternal need for it multiplies exponentially to support the growing baby and placenta.
Iron is the central building block of hemoglobin, the protein inside red blood cells responsible for carrying oxygen from the lungs to every tissue in the body. During pregnancy, a woman's body dramatically expands its blood volume, meaning she needs significantly more iron to manufacture extra red blood cells.
Pregnancy drastically alters a woman's iron metabolism. In the first trimester, iron requirements actually dip slightly because menstruation pauses. However, the second and third trimesters trigger a massive expansion in maternal plasma volume and red blood cell mass.
Because plasma volume increases faster than red blood cell count, a condition known as physiological anemia of pregnancy occurs, which is a normal dilutional effect rather than true iron deficiency. Despite this dilution, the absolute demand for stored and circulating iron climbs steadily to supply the fetus and placenta. If maternal stores are empty, the developing baby will actively draw what it needs, leaving the mother severely depleted.
Dietary iron exists in two distinct forms: heme iron and non-heme iron. Heme iron comes from animal tissues like beef, fish, and poultry, and it is easily absorbed by the human gut. Non-heme iron is found in plant foods such as beans, dark green leafy vegetables, and grains, and its absorption is much lower.
In many Nigerian households, plant-based non-heme sources form the bulk of the diet. Midwives must educate mothers on how to boost non-heme iron absorption by pairing it with vitamin C rich foods like oranges, tomatoes, or bell peppers. Conversely, substances like tannins in tea and phytates in unrefined grains can block iron absorption when consumed together with meals.
Routine antenatal screening is the cornerstone of preventing severe maternal complications. Midwives utilize the hemoglobin (Hb) test or the simple Tallquist scale in resource-limited settings to check blood status at booking and subsequent visits.
An Hb level dropping below 11 g/dL in the first or third trimester (or below 10.5 g/dL in the second trimester) indicates anemia. While low hemoglobin confirms anemia, it does not always prove iron deficiency on its own, as malaria, hookworm, and folate deficiency are also common co-factors in Nigeria. A thorough clinical assessment must look beyond lab values to include physical signs like conjunctival pallor, koilonychia, and persistent exhaustion.
Because diet alone rarely meets the soaring demands of gestation, routine iron and folic acid supplementation (IFAS) is a standard component of antenatal care across Nigeria. Midwives distribute standard tablets containing ferrous salts and folic acid to prevent neural tube defects and maternal anemia.
Effective counseling determines whether the woman actually swallows the tablets or discards them due to side effects. Midwives should instruct mothers to take iron tablets between meals or right before bedtime to maximize absorption and minimize stomach upset. Explaining that harmless dark green or black stools are a normal sign of unabsorbed iron excretion prevents unnecessary panic and improves compliance.
Gastrointestinal side effects are the single greatest barrier to successful iron supplementation. Many women experience nausea, epigastric discomfort, constipation, or diarrhea. When a mother complains of these issues, a midwife should avoid simply telling her to stop taking the medication.
Practical adjustments can resolve compliance barriers. Taking the supplement with a small amount of food (though it reduces absorption slightly), switching to a lower-dose preparation, or changing the specific iron salt can make a huge difference. For severe anemia unresponsive to oral pills, or when term is near and stores are critically low, midwives must recognize when to refer for parenteral (intravenous or intramuscular) iron therapy.