Pregnancy heartburn relief during pregnancy is a common concern many pregnant women have. Read on to see what you what remedies can be used to help relieve heartburn during pregnancy. /> What causes pregnancy heartburn? Heartburn in early pregnancy is a common complaint. The hormone progesterone is released as soon a woman becomes pregnant and can cause many early pregnancy symptoms which include pregnancy heartburn. Progesterone causes relaxation of the cardiac sphincter of the stomach which is the muscle between the stomach and the esophagus (food...