Can You Use GLP‑1 Medications While Breastfeeding? Here's What We Know

Many women who are breastfeeding wonder whether it's safe to take a GLP‑1 medication like Ozempic®, Wegovy®, or Mounjaro®. These medications have increased in popularity over the past few years, and there is a lot of interest - especially in women who are wanting to lost weight postpartum.

As a lactation consultant, I’ve had more and more moms ask about these medications. I’ve seen other lactation consultants recommend their use and even share their journey using them. Whether you're navigating postpartum weight concerns, managing type 2 diabetes, PCOS, or simply trying to feel more like yourself again, using these medications while breastfeeding can become a real question. But unfortunately... clear answers are hard to find.

That’s why I’ve broken down the latest research, especially from the InfantRisk Center (the leading authority on medication safety while breastfeeding), and created a balanced look at the pros and cons. Let’s dig into what we actually know about GLP‑1 medications and breastfeeding.

First—What Are GLP‑1 Medications?

GLP‑1 receptor agonists are a class of medications originally designed to help manage type 2 diabetes. These meds mimic a natural hormone that helps control blood sugar, slow digestion, and reduce appetite. Some of the most well-known GLP‑1s include:

• Semaglutide (Ozempic®, Wegovy®, Rybelsus®)

• Tirzepatide (Mounjaro®, Zepbound®)

• Liraglutide (Saxenda®, Victoza®)

They’ve become incredibly popular for weight loss - and they’ve also been touted recently as a treatment for PCOS - but if you’re breastfeeding, things get a little more complicated.

What the InfantRisk Center Says

The InfantRisk Center at Texas Tech University is the gold standard when it comes to research on medication and breastfeeding. They recently studied how much semaglutide (the active ingredient in Ozempic® and Wegovy®) passes into human milk - and the results were reassuring.

In their study:

• Semaglutide was not detected in any of the milk samples (tested for up to 24 hours after the injection).

• The estimated relative infant dose (RID) was less than 1.3%—well below the generally accepted safety cutoff of 10%.

• No adverse effects were observed in the breastfed babies involved in the study.

Translation? There’s very little—if any—transfer into breast milk for semaglutide injections, which is great news.

However, there’s little to no data on other GLP‑1 medications like tirzepatide (Mounjaro®) or liraglutide. Most of what we know about those comes from animal studies, which suggest the drugs do enter milk and may affect growth.

If you are considering any GLP-1 medications, it looks like semaglutide is likely the best option with the research we have - but it’s important to still approach this with caution.

Let’s Talk Pros and Cons

Here's a quick overview of pros and cons:

Potential Benefits

• Extremely low levels in breast milk (at least with injectable semaglutide)

• Improved maternal health - GLP‑1s can help with insulin resistance, blood sugar regulation, and even mental clarity. Many women who have milk supply issues also have insulin resistance, so if the use of GLO-1s can help lower weight and support blood sugar regulation, it may positively impact milk supply.

• Support with weight concerns - which can be incredibly motivating for some moms

• Expert backing – InfantRisk currently supports the safety of semaglutide while breastfeeding in specific situations

Potential Downsides

• Limited long-term data – we don’t yet know the effects of chronic exposure on babies over time

• Possible impact on milk supply – rapid weight loss and low calorie intake may lower supply for some women, especially if your diet isn’t being monitored carefully. When on GLP-1s, it is recommended to work with a nutritionist to ensure you are getting an increased amount of protein and other nutrients.

• Not all GLP‑1s are studied – tirzepatide and liraglutide haven’t been evaluated in lactating women

• Medication may interfere with birth control pills - leading to increased risk of pregnancy

What About Milk Supply?

This is where things get tricky.

Even if the medication itself doesn’t pass into breast milk, the way it works in your body might affect your supply - especially if you experience nausea, a reduced appetite, or rapid weight loss. Some moms report a dip in supply while using these medications, though this hasn’t been well studied.

If you’re already struggling with low supply, you may want to wait until breastfeeding is well established (often after 3–6 months postpartum) before starting a GLP‑1.

If you have insulin resistance, though, there may be a net-positive benefit to taking a GLP-1.

Regardless, it’s important to work with a lactation consultant and other healthcare providers as you navigate this to ensure you are support your supply and your baby as much as possible.

So… Can You Take a GLP‑1 and Breastfeed?

The short answer?

• If you’re using an injectable form of semaglutide, it’s likely safe while breastfeeding, especially if your milk supply is stable and baby is gaining well.

• For other GLP‑1s like Mounjaro®, we just don’t have enough human data yet. Most experts recommend caution or choosing alternatives.

As always, weighing your health needs alongside breastfeeding goals is essential. There's no one-size-fits-all answer, and you can consider your well-being in the equation.

Final Thoughts from an IBCLC

If you’re a breastfeeding mom considering a GLP‑1 medication, here are my top tips:

• Talk to your provider about semaglutide specifically - it’s the most studied option.

• Wait until your supply is stable, especially if you’re still in the early postpartum stage.

• Prioritize nutrition - if you’re eating very little or dropping weight quickly, supply can take a hit. Focus on quality protein sources, especially. The Milk Supply Kitchen meal plan has great recipes that can support this.

• Get lactation support - Make sure you are supporting your supply through this journey and addressing any underlying causes. If you’re already struggling with supply issues, support is key. My team is trained in complex milk supply issues and would love to help you - we are available worldwide. You can click here to request a consult.

Remember: You can care for your baby and take care of yourself.

Curious about your milk supply?

Check out The Low Supply Fix or take my Milk Supply Self-Assessment to figure out where you stand and how to optimize your supply—especially if you’re navigating medications or other health conditions.

💌 Questions? I offer 1:1 consults and messaging support—just comment "get help" and I’ll point you in the right direction.