Heartburn and Pregnancy

“Doctor! 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 gastro-esophageal 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.

The management of GERD during pregnancy involves many of the same principles as management in the non-pregnant state. Specifically, the so-called “lifestyle” changes should be meticulously followed. The two feet of the head of the bed should be raised on 6 to 8 inch blocks. Alternatively–and perhaps more conveniently–a 6 to 8 inch wedge-shaped foam rubber pad should be used to elevate the upper body. It is important that the foam be firm enough to truly elevate the upper body. The wedge should also extend all the way to the waist so that the entire chest is elevated. Lying on the left side at night may decrease acid reflux just as it does in non-pregnant patients with GERD. (In this position, it is physically more difficult for acid to reflux into the esophagus.) Occasionally, it may be necessary to sleep in a recliner chair at a 45-degree or greater angle. Any specific foods that aggravate heartburn should be avoided (e.g., coffee, cola, tea, alcohol, chocolate, fat, citrus juices, etc.) Frequent, small meals should be eaten rather than three large meals, and the last meal of the day should be early in the evening. After meals, pregnant women with heartburn should not lie down. After the evening meal, no further liquids should be consumed. (The more empty the stomach at bedtime, the less likely there will be reflux of acid.) Smoking, of course, should be discontinued for several reasons, including the fact that it aggravates reflux. Chewing gum also may be helpful. Chewing gum stimulates saliva which contains bicarbonate. The saliva and bicarbonate are swallowed,and the bicarbonate neutralizes the acid that has refluxed into the esophagus.

If lifestyle changes are not adequate, treatments with substances that are minimally absorbed into the body (and, therefore, not a potential threat to the fetus) should be started. Such treatments include antacids (e.g., Maalox, Mylanta), alginic acid/antacid combination (Gaviscon), and sucralfate (Carafate). The most reasonable starting regimen is antacids alone, one hour after meals and at bedtime. It may be necessary to alternate magnesium and aluminum-containing antacids to avoid diarrhea or constipation . If antacids are not effective alone, then the antacids should be continued and alginic acid/antacid added. The antacids and alginic acid/antacid should be taken after meals and at bedtime, more frequently if necessary.

If sucralfate is being used, it should be taken one-half hour before or after doses of antacids or alginic acid/antacid for maximal effect. (Sucralfate acts by coating and protecting the lining of the esophagus and stomach and is more effective in an acidic environment.) A small study in pregnant women has shown sucralfate to be successful in relieving heartburn. Further, studies in animals have not shown effects of sucralfate on the fetus.

Some antacids, alginic acid/antacid, and sucralfate contain aluminum, and small amounts of aluminum are absorbed into the body. However, the extra aluminum does not accumulate in the body unless there is impairment in the function of the kidneys, which normally excrete the excess aluminum. Therefore, absorption of aluminum probably does not represent a problem for the fetus unless the mother has kidney impairment.

Theoretically, magnesium-containing antacids could slow labor. (Intravenous magnesium has been used therapeutically to slow labor that is progressing too rapidly.) This potential problem, however, would only apply to magnesium-containing antacids taken just prior to labor and is not of concern earlier in pregnancy.

Antacids may interfere with iron absorption, and iron is important for the growing fetus. Nevertheless, pregnant women usually receive supplemental iron and a slight decrease in iron absorption (considering the use of supplements) should not result in a deficiency of iron. Moreover, insufficient iron intake or absorption is easily detected in blood tests as iron deficiency anemia.

If antacids, alginic acid/antacid, and sucralfate are not effective in controlling heartburn, probably the safest absorbed drugs that can be given are the H2 antagonists, specifically, cimetidine (Tagamet), ranitidine (Zantac), and famotidine (Pepcid). Although there are no studies in pregnant women, animal studies have shown no effects on the fetuses of pregnant animals. Nizatidine (Axid) should not be used because effects on the fetuses of animals have been shown, although at much greater doses than those used in humans.

Proton pump inhibitors are similar to the H2 antagonists with respect to their safety. Lansoprazole (Prevacid), rabeprazole (Aciphex), pantoprazole (Protonix), and esomeprazole (Nexium) have been shown to be safe when tested in pregnant animals, but because they are newer, experience with them is less than with the H2 antagonists. They should be used only when H2 antagonists in normal doses fail to control heartburn. Omeprazole (Cimetidine, Zegerid) probably should be avoided since although there are nostudies in pregnant womenshowing problems, it has been shown to have effects on the fetuses of animals at very high doses in some studies.

Concerns about the use of H2 antagonists and proton pump inhibitors are greatest during the first trimester when small drug-induced alterations in fetal development can result in major abnormalities at birth. Concerns are less during the second trimester and even less during the third trimester when most critical development of the fetus already has taken place.

Metoclopramide (Reglan) is used infrequently in treating GERD. Effects on the fetuses in animals has not been demonstrated and it can be used in pregnancy. Because of its neurologic side effects, however, it should be the drug of last resort.

 

This information is provided by MedicineNet.