Is omeprazole (proton pump inhibitor) safe to use in a pregnant patient?

Omeprazole Use in Pregnancy

Omeprazole can be safely used during pregnancy when clinically indicated, as available epidemiologic data fail to demonstrate an increased risk of major congenital malformations or adverse pregnancy outcomes. 1

Evidence Supporting Safety

The FDA drug label for omeprazole explicitly states that available epidemiologic data fail to demonstrate an increased risk of major congenital malformations or other adverse pregnancy outcomes with first trimester omeprazole use. 1

Large Population Studies

• A Swedish Medical Birth Registry study covering 955 infants exposed to omeprazole during pregnancy found that the number of infants with malformations, low birth weight, low Apgar scores, or hospitalization was similar to the general population. 1

• A Danish population-based cohort study of 1,800 live births with first trimester omeprazole exposure showed an overall birth defect rate of 2.9%, compared to 2.6% in unexposed mothers. 1

• A retrospective cohort study of 134 pregnant women exposed to omeprazole in the first trimester reported a malformation rate of 3.6%, compared to 4.1% in unexposed controls. 1

Treatment Algorithm for GERD in Pregnancy

Step 1: Lifestyle Modifications

• Begin with lifestyle modifications as first-line therapy for all pregnant patients with GERD symptoms. 2

Step 2: Calcium-Containing Antacids

• If symptoms persist, calcium-containing antacids are the preferred first-line medication. 2

Step 3: Sucralfate

• If heartburn remains uncontrolled with antacids, add sucralfate 1g orally three times daily. 2

Step 4: H2-Receptor Antagonists

• Escalate to histamine-2 receptor antagonists if sucralfate provides inadequate relief. 2

Step 5: Proton Pump Inhibitors

• When H2-receptor antagonists fail to control symptoms, step up to proton pump inhibitors (with omeprazole as the preferred agent due to the most extensive safety data), using antacids as rescue medication for breakthrough symptoms. 2

Clinical Experience and Long-Term Outcomes

• A case series of 9 women who received omeprazole during various stages of pregnancy (4 at conception, 5 starting between weeks 24-36) showed no severe side effects in mothers or newborns, with normal development in all children followed for 2-12 years. 3

• Omeprazole has been successfully used for refractory GERD during the third trimester when ranitidine and cisapride failed, with no apparent adverse fetal effects. 4

Important Caveats

While omeprazole is considered safe, it should be reserved for severe GERD that has not responded to lifestyle modifications, antacids, and H2-receptor antagonists. 2, 5

• Animal reproduction studies showed dose-dependent embryo-lethality at doses approximately 3.4 to 34 times the human dose of 40mg, though teratogenicity was not observed. 1

• Long-term PPI use in pregnancy should be avoided unless there is a proper indication, as chronic acid suppression may lead to vitamin and mineral deficiencies. 5

• The step-up approach ensures that the lowest effective intervention is used first, minimizing unnecessary medication exposure during pregnancy. 2