Mounjaro and Pregnancy – Do They Mix?

David Fuller

Last Updated On: October 20, 2025

Pregnancy is a time when every health decision carries extra weight, especially for those managing diabetes or obesity. With nearly 140 million births worldwide each year, many expectant mothers face complex choices about medication safety and how best to support both their own well-being and their baby’s development.

One medication now at the center of these conversations is Mounjaro (tirzepatide)—a once-weekly injectable therapy initially approved for type 2 diabetes and increasingly prescribed for weight management. As more people of childbearing age use Mounjaro, questions about its safety during pregnancy have become increasingly important.

Current health authority guidance, including from the U.S. Food and Drug Administration (FDA), advises against using Mounjaro during pregnancy due to limited human data and potential fetal risks observed in animal studies. Learn more about what’s currently known about Mounjaro’s use in pregnancy as we review available research and clinical insights.

Key Takeaways

• Mounjaro (tirzepatide) is not recommended during pregnancy due to potential fetal risks and lack of human safety data.
• Animal studies link tirzepatide exposure to growth restriction, skeletal abnormalities, and placental impairment.
• Insulin therapy is the first-line standard of care for diabetes management in pregnancy because it does not cross the placenta.
• Metformin and glyburide may be used only when insulin is not feasible, but both cross the placenta and require close monitoring.
• Patients should discontinue Mounjaro at least one month before conception to allow full drug clearance.
• Tirzepatide may reduce the effectiveness of oral contraceptives; non-oral or barrier methods are recommended after dose changes.
• Pregnant individuals who become pregnant while on Mounjaro should stop treatment immediately and consult their healthcare provider.

About: Operating since 2016, Med Supply Solutions is known for being one of the industry’s top and trusted suppliers of cosmetic and viscosupplementation products. If you’re looking to buy Mounjaro online, contact our sales department for more information.

Why Mounjaro Is Not Recommended During Pregnancy

Mounjaro (tirzepatide) influences the necessary metabolic hormones GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide). These regulate insulin secretion, appetite, and glucose metabolism. During pregnancy, these hormonal pathways already undergo natural changes to support fetal development. Introducing an external incretin-based drug can interfere with this balance, leading to unpredictable glucose fluctuations and potential harm to the fetus.

Intentional weight loss during pregnancy is also not advised. There are currently no randomized controlled trials supporting its safety, and observational data link gestational weight loss (deliberate or not) to a higher risk of small-for-gestational-age (SGA) infants. Because Mounjaro promotes weight reduction and appetite suppression, continued use could deprive the growing baby of necessary nutrients.

For these reasons, clinicians strongly recommend discontinuing tirzepatide at least one month before conception, allowing the body to clear the drug fully. This one-month window accounts for tirzepatide’s five-day half-life and is slightly shorter than the washout period for some other incretin therapies, such as semaglutide.

Animal Data and Safety Concerns Related to Mounjaro

Animal studies have raised clear concerns regarding Mounjaro’s pregnancy safety profile. Reproductive toxicology data from rat and rabbit studies showed:

• Fetal growth restriction, skeletal malformations, and embryo-fetal mortality at clinically relevant doses.
  
• Maternal weight loss and reduced food intake, potentially contributing to impaired fetal growth.
  
• Placental transfer of tirzepatide, suggesting possible direct fetal exposure.

Mechanistic studies also indicate that GLP-1 receptor activation may reduce placental nutrient transport by decreasing the labyrinth area and essential nutrient transporters, which could explain observed fetal growth restriction beyond maternal factors.

While no well-controlled human studies exist, small observational reports from other GLP-1 receptor agonists have not shown a definitive pattern of congenital anomalies. However, data remain too limited to establish safety for tirzepatide. Therefore, the FDA and other health authorities advise against Mounjaro use during pregnancy unless the potential benefits clearly outweigh the risks.

Nutritional and Fetal Risks of Mounjaro in Pregnancy

Mounjaro changes how the body processes nutrients, which may disrupt the delicate nutritional balance needed during pregnancy. These effects can lead to nutrient deficiencies, altered fetal glucose exposure, and developmental risks.

Key Concerns

• Appetite suppression and reduced calorie intake, potentially causing low birth weight or growth restriction.
  
• Fluctuating glucose levels, which may affect fetal insulin sensitivity and organ development.
  
• Exacerbation of nausea or vomiting, worsening morning sickness.
  
• Possible placental effects, given the role of incretin hormones in vascular and metabolic regulation.

Because fetal growth relies on steady maternal nutrition, continuing Mounjaro during pregnancy can undermine both maternal and fetal health. If pregnancy occurs unexpectedly, patients should stop Mounjaro immediately and consult a healthcare provider to transition to safer options.

Alternatives to Mounjaro for Managing Diabetes in Pregnancy

For pregnant individuals needing glucose control, insulin remains the gold standard and is recommended as first-line therapy for Type 1, Type 2, and Gestational Diabetes Mellitus (GDM). Insulin does not cross the placenta and allows dose adjustments based on gestational needs.

1. Insulin Therapy

• Safest and most effective option across all diabetes types in pregnancy.
  
• Enables individualized glucose control per trimester.
  
• Should be closely managed under obstetric and endocrinology care.

2. Metformin or Glyburide (Secondary Options)

• Sometimes used if insulin is not feasible, but both cross the placenta.
  
• Not ADA-preferred first-line treatments due to limited long-term safety data.
  
• Require close monitoring for maternal and fetal effects.

3. Nutrition and Lifestyle Management

• Balanced meals with complex carbohydrates, lean proteins, and healthy fats help maintain stable glucose levels.
  
• Frequent blood glucose monitoring supports individualized insulin adjustments.
  
• Moderate exercise (e.g., walking or prenatal yoga) improves insulin sensitivity and cardiovascular health.

For individuals transitioning off Mounjaro before conception, it’s vital to understand Mounjaro’s active ingredient and its pharmacokinetics. Any medication switch should be done gradually under the supervision of an endocrinologist or high-risk obstetrician to ensure both glycemic stability and fetal safety.

Conclusion

Mounjaro and pregnancy are not compatible. While tirzepatide’s dual GIP/GLP-1 mechanism represents a major advance in diabetes and obesity care, its impact on fetal development remains uncertain and potentially harmful. Because pregnancy requires precise metabolic balance and nutrient supply, continuing tirzepatide poses unnecessary risks to both mother and child.

Women of reproductive potential should:

• Use reliable contraception while taking Mounjaro or Zepbound.
  
• Be aware that tirzepatide reduces the effectiveness of oral hormonal contraceptives due to delayed gastric emptying—non-oral or barrier methods are recommended for four weeks after starting or after each dose increase.
  
• Discontinue Mounjaro at least one month before trying to conceive.
  
• Seek medical advice immediately if pregnancy occurs while on treatment.

Healthcare professionals play a critical role in helping patients transition to safer therapies and plan pregnancies responsibly. Open communication ensures timely medication adjustments, better outcomes, and protection for both mother and baby.

FAQs

1. Can you take Mounjaro while pregnant?

No. Mounjaro should not be used during pregnancy due to a lack of human safety data and animal studies showing fetal harm.

2. What is the tirzepatide pregnancy warning?

Tirzepatide carries a warning advising discontinuation before conception. It is contraindicated during pregnancy unless no safer alternative exists.

3. What if I become pregnant while using Mounjaro?

Stop Mounjaro immediately and contact your healthcare provider. They will recommend safer options such as insulin therapy.

4. Can Mounjaro affect fertility or birth outcomes?

There is no evidence that it directly impacts fertility. However, its potential effects on fetal growth and placental function make it unsafe for pregnancy.

References

Eli Lilly and Company. MOUNJARO (tirzepatide) Injection, for subcutaneous use. Highlights of Prescribing Information. US Food and Drug Administration. Updated May 2022. https://www.accessdata.fda.gov/drugsatfda_docs/label/2022/215866s000lbl.pdf

Dang V. Mounjaro and pregnancy, breastfeeding, and birth control. Medical News Today. https://www.medicalnewstoday.com/articles/drugs-mounjaro-reproductive-heath

Parker CH, Slattery C, Brennan DJ, Roux CWL. Glucagon‐like peptide 1 (GLP‐1) receptor agonists’ use during pregnancy: Safety data from regulatory clinical trials. Diabetes Obesity and Metabolism. Published online May 6, 2025. doi:10.1111/dom.16437

Finkle J, Brost BC. Role of Glucagon-Like peptide-1 receptor agonists in people with infertility and pregnancy. Obstetrics and Gynecology. Published online January 23, 2025. doi:10.1097/aog.0000000000005825