Heartburn During Pregnancy

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"Doctor Jay! What can I do? I'm burning up!"

Linda was 7 months pregnant and the heartburn was overwhelming. To her, it seemed constant. She couldn't lie down at night. The discomfort of her bulging belly was nothing in comparison.

Linda has a lot of company. Heartburn (a symptom of gastroesophageal reflux disease or GERD) occurs in one-quarter to one-half of all pregnant women. It usually begins in the first or second trimester of pregnancy and continues throughout the remainder of the pregnancy. Fortunately, the heartburn is usually mild and intermittent, but frequently enough, it is troublesome or severe. Complications of GERD (esophageal bleeding, trouble swallowing, loss of weight, etc.) are uncommon. In non-pregnant circumstances, heartburn is easily and successfully treated since there are several types of medication that are highly effective in relieving heartburn. The problem is that we do not know how safe these medications are for the developing fetus, and no one is going to test them in pregnant women to find out! About the best we can do is test them in pregnant animals at doses much higher than would ever be used in humans.

The cause of GERD during pregnancy is a bit more complicated than in the non-pregnant state. The basic cause--reflux of acid from the stomach into the esophagus--is the same. Similar to the situation with GERD in the non-pregnant state, the lower esophageal sphincter (the muscle at the lower end of the esophagus that normally prevents acid from refluxing) is weak in pregnancy. This probably is an effect of the high levels of estrogens and especially progesterones that are part of pregnancy. This weakness resolves after delivery. It is not known whether unexplained, transient relaxations of the sphincter, a common cause of reflux in the non-pregnant state, also occur in pregnancy. It also is not known if the contraction (motility) of the esophagus above the sphincter--a common contributor to GERD in the non-pregnant state--is impaired in pregnancy and is responsible for delaying the clearance of acid from the esophagus back into the stomach. What makes pregnancy different is the distortion of the organs in the abdomen and the increased abdominal pressure caused by the growing fetus. These changes clearly promote the reflux of acid.

Heartburn and Pregnancy Resources

Doctor written main article on Heartburn (Reflux)

Medically Reviewed by a Doctor on 12/2/2013