The marker used by researchers to diagnose iron deficiency, hemoglobin, which tells one the number of red blood cells in the body has been shown to be set too high. This is evidenced in women with pre-eclampsia, the marker for adverse effects in the unborn child, hemoglobin, when it is in the normal range women manifest pre-eclampsia but women who are 'anemic', do not manifest pre-eclampsia, at all, 0%.
"a hemoglobin value below 11.0 g/dL excluded the risk for severe preeclampsia to 100%."

Diabetes rate too is affected by this mistaken diagnosis due to higher than required hemoglobin.

"The prevalence of GDM is reduced in iron deficiency anemia"