Hi Morgaine, thanks for the references, that's really interesting reading!

It appears there's an optimal haemoglobin level during pregnancy in terms of risk to the baby, and that above and below this, the risks increase. I found a Chinese study which looked at the relative risk of preterm birth and low birth weight, and the lowest relative risk was in the group with Hb 120-129. The highest relative risk was in the group with Hb of 60-89 (pretty low) - roughly 3 times the risk of the above group. An English study by Little found a similar pattern, but the group they stated was at lowest risk was 90-110. The study by Steer certainly suggested max birthweight with Hb 85-95 (as their lowest measurement during pregnancy) - it also said that "the lowest incidence of low birthweight and preterm labour occurred with a lowest Hb concentration of 95-105".

Wow, what an interesting set of articles!!!!! This is really interesting for someone like me who has genetically high iron levels and has never had anaemia. I'll be interested to see what outcome I have!