Iron in pregnancy

Also see Iron distribution, Iron

During pregnancy

• Total body iron requirement is increased by 1000mg
• From 20 weeks onwards, mother takes up 6-7mg/day
• Late trimeter, the foetus takes up 4mg/day from the mother

NB:

• Normal female total iron store
  = 2000 to 2500 mg
• Normal daily iron absorption
  = 1 to 2 g/day
• [PK1:p240] Absorption of dietary iron increase from 5-10% to 20-30% in pregnancy or iron-deficient state

Transfer of iron

• Iron crosses the placenta against a concentration gradient
• Iron transfer from the mother to foetus is not affected by maternal iron deficiency unless very severe

Maternal transferrin (with Fe3+ iron)
--> Uptake by transferrin receptors in trophoblast cells
--> Iron transported across the placenta
--> Released into the umbilical capillary
--> Binds with foetal transferrin in foetal circulation