Yes, it is possible to take too much iron during pregnancy. The upper limit of iron added up from both food and supplementation is 45mg per day. Excessive iron supplementation may lead to troubling side effects such as nausea, vomiting, severe abdominal pain, inflammation of the stomach lining and ulcers. Too much iron can also reduce absorption of the essential mineral, zinc. However, if you have been diagnosed with iron deficiency anemia, your doctor may prescribe higher levels of iron supplementation (over the upper limit) until your blood levels are brought back to normal.