The RDA (recommended dietary allowance) of iron for pregnant women is 27 mg daily, compared with 18 mg for non-pregnant women. During pregnancy a women not only increases her own blood supply, she also gives her baby the iron needed to support his growth before birth and gives him supplemental stores which will help his growth in early infancy.
Iron deficiency can cause premature delivery as well as leading to low birth weight infants. Yet a recent study in Britain (where prenatal vitamins are not routinely recommended) found that 80% of women had inadequate iron intake (Hum Reprod 2011;26(4):911-9).
There are two types of iron in food. The most efficiently absorbed iron (heme iron) comes from animal products. Vegetarian sources (non-heme iron) are abundant in a healthy diet and also important sources of iron. Fortified products (such as breakfast cereals) use non-heme iron. It is possible to get adequate iron with a vegetarian diet.
Your obstetrician will likely recommend a prenatal vitamin with iron. If a blood test shows you have a low hemoglobin level, she will also recommend supplemental iron. These can be an important part of a healthy pregnancy. However, realize that a vitamin pill can only ever be a supplement. It can only assist a good quality diet, it will never take its place.
A healthy diet that includes iron rich foods is essential during pregnancy. Here’s a handout with a list of iron-rich foods.
If your doctor advises an iron supplement, here are some pointers.
Sometimes supplemental iron can cause constipation or nausea. If you are already suffering from pregnancy nausea or discomfort, you won’t want added discomfort. Try reducing your iron dose and then increasing it gradually.
If that doesn’t solve the problem, try a different iron source. Many supplements are ferrous sulfate. This is a good source, but if it causes problems for you, try a supplement that uses ferrous fumarate. If that doesn’t work, try ferrous gluconate.
The proteins in meat will help you absorb iron, as will foods rich in vitamin C, such as citrus, peppers, or tomatoes.
Don’t take iron supplements with tea: tea has tannins which interfere with the absorption of iron. Substances in beans and whole grains can interfere as well. If your obstetrician also recommends a calcium supplement, don’t take your calcium and iron together, as appears that calcium may interfere with iron absorption.
Keep iron supplements out of the reach of children. Iron can be toxic in relatively small doses.
This section contains articles and guidance for healthy eating whether you are working on becoming pregnant, expecting or have a new baby. Articles cover information including what to eat, controlling nausea, breastfeeding and vitamins.