Gastroesophageal reflux , appearing mainly as retrosternal heartburn, is observed in 40-80% of pregnancies. Most patients experience symptoms at the end of the first trimester and these become worse as the pregnancy progresses.
What factors contribute to the onset of symptoms?
- In the 2nd and 3rd trimester of pregnancy, mainly due to the action of progesterone, the pressure of the lower esophageal sphincter (that is, the valve between the esophagus and the stomach) decreases, thus facilitating reflux.
- The increase in intra-abdominal pressure, as the fetus grows, and the delayed emptying of the stomach, which is also observed in pregnancy, also contribute to reflux.
What are the symptoms?
Most patients experience retrosternal burning (heartburn), regurgitation and discomfort, especially after meals or when lying down. Complications of reflux disease, such as esophagitis or esophageal stricture, are very rare, and this is because the reflux is of short duration.
How is reflux diagnosed in pregnancy?
The diagnosis of reflux in pregnancy is based on the patient’s symptoms. There is a need for a gastroscopy only when the symptoms are very severe and resistant to the usual treatment and when reflux complications are suspected.
Gastroscopy can be performed safely in the pregnant woman with appropriate monitoring of arterial oxygen and pulses. We prefer not to administer midazolam (dormicum), but pethidine or propofol, which are safer for the fetus.
The great challenge for the gastroenterologist is the treatment of reflux in pregnancy. This is where proper nutrition can have a positive effect. Patients with mild associated symptoms will benefit only with a change in diet and lifestyle. Eating small and frequent meals, elevating the head of the bed, avoiding foods that either relax the gastroesophageal valve or increase stomach acid, and avoiding lying down after meals are some simple measures that provide relief for many patients.
In more severe cases, the doctor should discuss with the patient the benefits and risks of medication. For most drugs, for ethical and legal reasons, there are no data from randomized controlled trials regarding their safety in pregnancy.
We know that the period of teratogenesis mainly concerns days 31-71 (in a 28-day cycle) from the last menstruation, i.e. mainly the first 10 weeks of pregnancy, because that is when organogenesis actually takes place. More generally, unless there is an urgent need, the administration of drugs should be delayed and started after this critical period.
Dealing with reflux
In terms of treating reflux, the drugs we use are: antacids, histamine receptor antagonists, sucralfate, promotor drugs and proton pump antagonists.
Antacids act quickly and temporarily relieve symptoms. Calcium and magnesium-based antacids can be safely used in pregnancy, unlike those containing sodium bicarbonate, which should be avoided. Alginate drugs are also safe as their absorption is minimal. Antacids should not be taken together with iron preparations.
Sucralfate is safe during pregnancy as its absorption is extremely low.
Histamine receptor antagonists
These drugs (ranitidine, cimetidine, famotidine, nizatidine) are the most widely administered drugs in pregnancy and show an extremely safe profile. With the exception of nizatidine, for which there are some questions (although it is also approved by the US Food and Drug Administration), the remaining histamine antagonists can be used safely in pregnancy.
Metoclopramide, mainly used to treat nausea and vomiting in pregnancy (by increasing the pressure of the lower esophageal sphincter), is a safe drug.
Proton pump inhibitors
Proton pump inhibitors (omeprazole, esomeprazole, pantoprazole, lansoprazole, rabeprazole) are clearly more effective drugs, both for the treatment of reflux symptoms and for the treatment of possible esophagitis. The data from studies are not so many, but it seems that they are not related to teratogenesis and can be safely used in pregnancy, especially after the first trimester and when other therapeutic measures have failed.
In most pregnant women, reflux symptoms subside after delivery, but in a few, they remain. If the woman is going to breastfeed, she should know that:
- Magnesium and aluminum based antacids are safe while breastfeeding. The same is true with sucralfate and alginate drugs. Cimetidine/ranitidine is safe unlike nizatidine which should be avoided
- Data on proton pump inhibitors are limited and therefore should not be used during breast-feeding.