Iron in pregnancy
[KB2:p201]
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