Although you may go on living your normal life despite having low iron in your blood, sometimes serious health situations can arise due to this. To compensate for the lack of oxygen in your body, your heart must pump in more blood. Your heart is after all a muscle. With extra hard work, it begins to grow and an enlarged heart can lead to heart failure. During pregnancy, iron deficiency can lead to premature birth or babies with low birth weight. With low iron, children may not grow properly and may suffer from stunted growth as well as a compromised immunity against diseases and infections.