How Gestational Diabetes Affects Glucose Transfer to Your Baby

Welcome back, Mamas!

Managing gestational diabetes (GDM) brings new challenges and plenty of questions. One common worry I often get asked is whether having GDM means baby also has diabetes.

The short answer?

No—gestational diabetes affects only the mother, not the baby.

Understanding how your body and the placenta work together to support your baby can hopefully bring some peace of mind. In today's blog, we’ll look at how glucose moves to the baby, why insulin doesn’t cross the placenta, and what this means for both you and your little one’s health.

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Our mission is to help you maintain healthy blood sugar levels and make informed choices for your health and your baby’s well-being.

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Now back to it...

How Glucose Crosses the Placenta

Think of the placenta as a bridge connecting you and your baby, delivering nutrients and oxygen to help your baby grow strong and healthy. Glucose is one of the main sources of energy that crosses this bridge from you to your baby.

When you eat, your body breaks down carbohydrates into glucose, which then enters your bloodstream. From there, glucose can easily cross the placenta to reach your baby, supplying them with the energy needed for growth and development.

This process is natural and important for your baby’s growth. However, with gestational diabetes, blood sugar levels can be higher than usual, which means more glucose might be crossing to the baby.

This is why managing your blood sugar is key; it keeps this flow of energy balanced, helping your baby get what they need without extra challenges.

Why Insulin Doesn't Cross the Placenta

While glucose is small and passes through the placenta easily, insulin—a hormone produced by your pancreas to help regulate blood sugar—is a much larger molecule.

Due to its size, insulin cannot cross the placenta.

This means that your insulin stays on your side, while your baby produces their own insulin to handle the glucose they receive from you.

This is good news! It means that you and your baby each have separate insulin systems. Your body handles the work of regulating blood sugars for you, and the baby’s body will regulate their own blood sugars as needed.

Even though gestational diabetes causes higher blood sugar levels, it only affects your abilty to store blood sugar away, not your baby.

How Mom’s Blood Sugar Affects Baby’s Insulin Production

Since the baby receives glucose from the mother’s blood, when your blood sugar is high, your baby receives more glucose. To manage this extra glucose, your baby’s pancreas produces more insulin.

Insulin is a growth hormone, so when the baby produces extra insulin to handle the extra glucose, it can lead to more fat storage. This process is why babies of mothers with untreated or poorly controlled gestational diabetes are sometimes larger at birth.

The good news is that by keeping your blood sugars in the target range, you’re helping regulate the amount of glucose reaching your baby, which supports healthy growth and lowers the risk of your baby storing excess fat.

This is one of the main reasons why managing gestational diabetes through lifestyle changes and, if needed, medication is so important—it benefits both you and your baby!

The Takeaway

Learning how your body and your baby’s body work together during pregnancy can hopefully bring just a bit more peace of mind. By keeping your blood sugars balanced, you’re already making a positive impact on your baby’s growth and development.

Remember, each step you take, every balanced meal, and the care you put into managing your health is a meaningful effort.

You’re doing an amazing job, Mama! Keep it up!

Until next week!

Disclaimer: The information provided in this blog post is intended for general informational and educational purposes only. It is not intended to replace or substitute professional medical advice, diagnosis, or treatment. Always seek the advice of your healthcare provider with any questions you may have regarding a medical condition or your health. Never disregard professional medical advice or delay seeking it because of something you have read in this blog. GDMamas, LLC assumes no liability for inaccuracies, errors, or omissions in the information presented.