Are Glucagon-like peptide-1 (GLP-1) medications safe to take during pregnancy?

GLP-1 Medications During Pregnancy: Safety Considerations

GLP-1 receptor agonists should not be used during pregnancy as they lack adequate safety data and are not recommended by clinical guidelines.

Current Recommendations

The American Diabetes Association (ADA) provides clear guidance on medication use during pregnancy:

• Insulin is the preferred agent for managing both type 1 and type 2 diabetes during pregnancy 1
• Metformin and glyburide should not be used as first-line agents as they cross the placenta 1
• Other oral and noninsulin injectable glucose-lowering medications (including GLP-1 receptor agonists) lack long-term safety data for use in pregnancy 1
• When metformin is used for polycystic ovary syndrome to induce ovulation, it should be discontinued by the end of the first trimester 1

Evidence on GLP-1 Receptor Agonists in Pregnancy

Animal Studies

Animal studies have shown concerning effects of GLP-1 receptor agonists during pregnancy:

• Reduced fetal weight and/or growth
• Delayed ossification and skeletal variants
• Potential embryonic death 2

These effects were often associated with reduced maternal weight gain and decreased food consumption in the animal models 2.

Human Data

Human data on GLP-1 receptor agonist use during pregnancy is extremely limited:

• A 2023 systematic review found only 76 documented human offspring with exposure to these medications 2
• A 2024 observational study of 168 pregnancies with first-trimester GLP-1 exposure did not show increased risk of major birth defects compared to reference groups, but the sample size was limited 3
• Case reports have described normal pregnancy outcomes after first-trimester exposure, but these are anecdotal 4

Medication Safety During Pregnancy

The general approach to medication use during pregnancy follows these principles:

• Medications should be avoided during pregnancy unless the benefits clearly outweigh the risks 5
• For diabetes management specifically, insulin is considered the safest and preferred option 1
• All GLP-1 receptor agonists should be discontinued before pregnancy or immediately upon pregnancy detection 6

Recommendations for Women Taking GLP-1 Receptor Agonists

1. Women planning pregnancy:

   • Discontinue GLP-1 receptor agonists before attempting conception
   • Transition to insulin therapy if diabetes treatment is needed
   • Use effective contraception while taking GLP-1 receptor agonists 6

2. Women with unplanned pregnancy while on GLP-1 receptor agonists:

   • Discontinue the medication immediately
   • Consult with healthcare provider for transition to insulin therapy
   • Discuss potential risks with healthcare provider, recognizing limited data on human outcomes

3. Alternative treatments during pregnancy:

   • Insulin is the preferred medication for managing diabetes during pregnancy 1
   • Lifestyle modifications (diet, exercise) are essential components of gestational diabetes management 1

Conclusion

While recent observational data provides some reassurance about first-trimester exposure 3, the lack of comprehensive safety data and clear guideline recommendations against their use means GLP-1 receptor agonists should not be used during pregnancy. Women should be counseled about effective contraception while taking these medications and should transition to insulin therapy if pregnancy occurs or is planned.