Proton Pump Inhibitors


The information provided below is for readers based in the United States of America. Readers outside of the United States of America should seek the information from local sources.


Proton pump inhibitors (PPIs) have been associated with an increased risk of birth defects when used within 4 weeks prior to conception. Additionally, PPIs taken during pregnancy can increase the chances that your baby will develop childhood asthma.

What are proton pump inhibitors?

PPIs are medications used to decrease stomach acid. Certain diseases cause stomach acid to move in the wrong direction and into your esophagus, which is the tube that moves food from your mouth to your stomach. This can result in symptoms of bitter taste, coughing, sore throat, and heartburn, a burning sensation in your throat or chest that usually occurs after eating. You can read more about heartburn during pregnancy here. Types of PPIs that are available include omeprazole (Prilosec), esomeprazole (Nexium), pantoprazole (Protonix), lansoprazole (Prevacid), dexlansoprazole (Dexilant), and rabeprazole (AcipHex). Of the available PPIs, omeprazole, esomeprazole, and lansoprazole can be purchased without a prescription.

Proton pump inhibitors are used to treat:

PPIs are used to treat gastroesophageal reflux disease (GERD). They can also be used as part of a treatment plan for ulcers or to heal damage to the esophagus that occurs from long-term exposure to stomach acid.

What is GERD?

There is a muscle located at the end of your esophagus that separates the esophagus from the stomach. In GERD, this muscle does not work properly and allows acid to flow backwards from the stomach into the esophagus, a condition known as acid reflux. If you have acid reflux, you may experience heartburn or have a sour taste in the back of your throat. Your doctor may suspect that you have GERD if you have acid reflux that occurs at least twice per week and lasts for several weeks. People with GERD may injure their esophagus because it is being continuously exposed to stomach acid. Additionally, GERD can produce more serious symptoms, such as vomiting, coughing, difficulty swallowing, pain in your upper chest, and lung problems. During pregnancy, changes in your bodys hormones can increase the likelihood that you will develop GERD. You can read more about GERD during pregnancy here.

How do proton pump inhibitors work?

PPIs reduce the amount of acid that your stomach can release. This decreases the amount of stomach acid that your esophagus is exposed to if acid reflux occurs. PPIs provide relief from symptoms of acid reflux and allow damaged tissue in the esophagus to heal. PPIs are most effective when taken 30 minutes before your first meal of the day. They are also more effective when taken every day, instead of taking them only when you experience heartburn.

If I am taking a proton pump inhibitor, can it harm my baby?

PPIs can increase the risk of birth defects if they are taken prior to the date that you become pregnant. Although taking a PPI prior to conception has been associated with birth defects, there has not been enough evidence to determine if taking a PPI during the first trimester further increases the risk of birth defects. Most studies show that PPIs taken during the first trimester do not increase the risk, however, there are some independent reports that show an increased risk may be possible. Additionally, further evidence has shown that taking a PPI during pregnancy can increase the chances that your baby will develop asthma at some point during his or her childhood.


A study published in the New England Journal of Medicine analyzed pregnancy outcomes from 5082 expecting moms who took a PPI between 4 weeks prior to conception and the end of the first trimester of pregnancy. PPIs did not have an increased risk of birth defects when used during the first trimester of pregnancy. However, there was an increased risk of birth defects, specifically heart and urinary tract defects, when a PPI was taken within 4 weeks prior to becoming pregnant. Lansoprazole was the only PPI associated with this increased risk of birth defects. This analysis was one of the largest to date and included expecting moms taking omeprazole, pantoprazole, lansoprazole, rabeprazole, and esomeprazole.

Several other studies have found that PPIs were not associated with an increased risk of birth defects when used during pregnancy (after conception), including: 1530 expecting moms who used a PPI during pregnancy; 593 expecting moms who used a PPI (the majority used omeprazole) during the first trimester of pregnancy; 410 expecting moms who took a PPI during pregnancy (the majority used the PPI during their first trimester), including 295 who took omeprazole, 62 who took lansoprazole, and 53 who took pantoprazole; 113 expecting moms who used omeprazole during the first trimester of pregnancy; and 1186 expecting moms who used a PPI during the first trimester of pregnancy. This last study also concluded that using a PPI during the third trimester did not increase the risk of premature delivery, death of the baby, or low birth weight.

A study that analyzed 955 pregnancy outcomes from the Swedish Medical Birth Registry did find that there was a slightly higher percentage of stillborn babies and babies born with heart defects in pregnant women who used omeprazole during pregnancy. However, the authors concluded that this small increase compared to the general population could have been by chance, and that overall, omeprazole taken during pregnancy was not associated with an increased risk of negative pregnancy outcomes.

Additional evidence exists from a smaller study that may link the use of PPIs during pregnancy with a specific type of birth defect. The study involved 7 expecting moms and showed that the use of PPIs during pregnancy was associated with a urinary tract defect in baby boys. However, these results conflicted with another much larger study involving 2926 baby boys whose moms took a PPI during pregnancy, which concluded that there was not an increased risk for this particular defect.

In addition to the risk of birth defects, expecting moms who take PPIs during pregnancy may increase the chances that their baby will develop childhood asthma. This evidence was found in 2 studies that each included at least 2000 children whose moms used a PPI during pregnancy.  Both of these studies determined that taking a PPI during pregnancy increased the chance that the baby would develop childhood asthma by up to 41%. 

If PPIs are used during pregnancy, it is not recommended to use newer agents, including esomeprazole, rabeprazole, or dexlansoprazole, because they have little safety data available.  Most of these studies focused on omeprazole and therefore, it is often considered to be the preferred medication in expecting moms. Some PPIs also contain sodium bicarbonate, an ingredient that should not be used during pregnancy.

Bottom line: When taken during pregnancy, PPIs may increase the risk of your baby developing childhood asthma. You should avoid taking PPIs prior to conception because they have been associated with an increased risk of birth defects.

If I am taking a proton pump inhibitor and become pregnant, what should I do?

If you are taking a PPI and become pregnant, you should contact your doctor immediately. While many studies have considered PPIs to have a low risk for negative outcomes in babies, the risk of birth defects is still unclear and cannot yet be ruled out. PPIs can also increase the risk that your baby will develop childhood asthma. Your doctor may decide to discontinue your PPI until after your delivery to ensure the safety of your baby.

If I am taking a proton pump inhibitor, can I safely breastfeed my baby?

There is very little data available on the effects of PPIs on the breastfed baby. The evidence that is available suggests that these medications do not cause harm to the baby. One mother taking omeprazole every day pumped and discarded her br
east milk 4 hours after her omeprazole dose and continued to breastfeed her baby throughout the rest of the day without any negative effects observed in her baby.  Both omeprazole and pantoprazole have been shown to pass into milk in low amounts.  There is no other data available on the use of PPIs while breastfeeding. Due to the lack of safety information and potential concerns that PPIs could interfere with your babys digestion, it is recommended to avoid the use of PPIs when breastfeeding until more evidence is available. 

Bottom line: PPIs should be avoided while breastfeeding due to the lack of available safety information.

If I am taking a proton pump inhibitor, will it be more difficult to get pregnant?

No studies have been conducted on the effects of PPIs on a womans fertility; however, some evidence has shown that PPIs may interfere with a mans ability to father a child. A study showed that men who had used a PPI 6 to 12 months before a semen analysis had a 3 times higher risk of having low sperm counts. This data conflicted with another study that showed that the use of PPIs 3 months prior to a semen analysis did not lower sperm count in men. However, the men in this study already had fertility problems prior to the start of the study.  Men that are taking a PPI and are trying to father a child should contact their doctor. Their doctor may decide to discontinue the medication until they have successfully fathered a child.

If I am taking a proton pump inhibitor, what should I know?

PPIs are not recommended prior to conception. If you are planning to become pregnant, you should contact your doctor to discuss your pregnancy plans. There has been some evidence that PPIs, particularly lansoprazole, increase the risk of birth defects when used within a few weeks prior to becoming pregnant. If your doctor determines that a PPI is necessary to control your symptoms, omeprazole may be a better option since there is more safety data available for it.

It is recommended to avoid PPIs during pregnancy (after conception) unless they are necessary to control your symptoms. Using a PPI during pregnancy can increase the risk that your baby will develop childhood asthma. Additionally, although most studies have concluded that the use of PPIs during pregnancy is not associated with a higher chance of birth defects, the exact risks of PPIs in pregnancy are still unclear.

PPIs should be avoided while breastfeeding because there is little data available on their safety in the breastfed infant.

PPIs may need to be discontinued in men who are trying to father a child. PPIs can interfere with a mans fertility by reducing sperm count. Men who are using a PPI and are trying to father a child should contact their doctor to determine if the PPI should be temporarily discontinued.

If I am taking any medication, what should I know?

All pregnancies have some risk for having a miscarriage, a baby with a birth defect, or other poor birth outcomes regardless of medical conditions or drug exposures. There is no absolutely safe medication for all pregnant women, but sometimes a medical condition can be more harmful than the drugs that are available to treat it. Always consult a health care professional about medications and other treatment options that you may need during your pregnancy to determine what is best for you and your baby.

The information in this report is not intended as a substitute for the advice and care of your doctor or other health care provider. Always consult your doctor before you take or stop taking any medications during your pregnancy and while you breastfeed.

This report provides a summary of available information about the use of PPIs during pregnancy and breastfeeding. Content is from the product label unless otherwise indicated.


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General information

It is very common for women to worry about having a miscarriage or giving birth to a child with a birth defect while they are pregnant. Many decisions that women make about their health during pregnancy are made with these concerns in mind.

For many women these concerns are very real. As many as 1 in 5 pregnancies end in a miscarriage, and 1 in 33 babies are born with a birth defect. These rates are considered the background population risk, which means they do not take into consideration anything about the health of the mom, the medications she is taking, or the family history of the mom or the baby’s dad. A number of different things can increase these risks, including taking certain medications during pregnancy.

It is known that most medications, including over-the-counter medications, taken during pregnancy do get passed on to the baby. Fortunately, most medicines are not harmful to the baby and can be safely taken during pregnancy. But there are some that are known to be harmful to a baby’s normal development and growth, especially when they are taken during certain times of the pregnancy. Because of this, it is important to talk with your doctor or midwife about any medications you are taking, ideally before you even try to get pregnant.

If a doctor other than the one caring for your pregnancy recommends that you start a new medicine while you are pregnant, it is important that you let them know you are pregnant.

If you do need to take a new medication while pregnant, it is important to discuss the possible risks the medicine may pose on your pregnancy with your doctor or midwife. They can help you understand the benefits and the risks of taking the medicine.

Ultimately, the decision to start, stop, or change medications during pregnancy is up to you to make, along with input from your doctor or midwife. If you do take medications during pregnancy, be sure to keep track of all the medications you are taking.