Midwife and diabetes educator JULIE DAWSON shares her personal experience of breastfeeding with type 1 diabetes, and what you need to keep in mind.  

Are you living with type 1 diabetes and wondering if you can breastfeed your baby? Yes, you absolutely can. 

Be aware that your insulin requirements will change throughout the pregnancy, during labour and in the postpartum period and seek support early. Before you even fall pregnant, ask for a referral to an endocrinologist or obstetrician and credentialled diabetes educator to talk through your pre-conception care. This will ensure that your glucose levels are in target and you are receiving the right pre-pregnancy supplements.   

A credentialled diabetes educator and a lactation consultant can follow you through your journey to support a healthy pregnancy and breastfeeding experience.  

My experience of breastfeeding with type 1 diabetes  

My personal experience as someone living with type 1 diabetes was that breastfeeding was extremely challenging but had so many health benefits for me and my baby.  

One thing I was not aware of was that my insulin requirements would reduce significantly after giving birth and while I breastfed.  

This was 15 years ago, before continuous glucose monitors. I relied on my symptoms of sweating, shaking and feeling nauseous, then would test by fingerprick to confirm.  I managed my hypos by drinking lemonade, but soon learned to prevent them where possible by eating more carbs and adding protein shakes between meals.  

I had to educate my five-year-old daughter on how to call 000 so she knew what to do if ever she found me unconscious. I also kept a lunchbox of jellybeans in the cupboard for hypo treatments that my daughter could reach if I asked for them. It was a scary time, but I never got below 2.6mmol/L and never had a hospital admission.  

Here’s an overview of what you can expect. 

During pregnancy 

Your insulin requirements will increase up to the end of your third trimester. 

Labour and delivery 

Throughout labour, it is recommended keeping blood glucose levels between 4 and 7mmol/L. If your blood glucose levels rise higher than 10mmol/L, then it’s recommended to check for ketones to detect diabetic ketoacidosis (DKA.)  

The postpartum period 

Immediately following the delivery of your baby and the placenta, there is a significant reduction in insulin required – up to 30% less basal insulin. 

If you choose to breastfeed, milk production uses insulin continuously, even between feeds. 

A diabetes educator can help titrate basal insulin doses to prevent the risk of hypos, especially overnight, due to increased insulin sensitivity related to breastfeeding. Cluster feeding, which is when your newborn feeds intensively to boost your supply, can lead to drops in blood glucose levels of up to 2.2mmol/L. 

However, once breastfeeding is established, at around three months, your insulin requirements will stabilise. 

You are also likely to experience fewer post-meal spikes in your blood glucose levels because the mammary glands take up the glucose in your food for milk production, so you can reduce bolus insulin by 10-20%. You may need to reduce your ICR (insulin to carbohydrate ratio) if you are still experiencing lows. 

Preventing lows during breastfeeding 

•  Snack if your blood glucose levels are falling or less than 5mmol/L before a breastfeed and keep a carbohydrate snack by your bedside. 

• Use CGM trending arrows to see the direction and speed of any blood glucose changes to help with management. 

• Set your CGM alarm higher for the low target (this ensures lows are picked up early, which ensures safety when caring for a newborn and reduces the risk of falls when carrying your baby.) 

• Set up a portable station with water, snacks and hypo treatments that can be moved to wherever you breastfeed in the house.  

• Remember the ‘don’t drive under 5.0mmol/L rule’ – always check your CGM or fingerprick before driving a car. 

• Add more protein and low-GI carbohydrates to meals with healthy fats to maintain health and milk supply. 

Why does breastfeeding use so much glucose? 

There are a number of reasons for this. One is that the cells in the mammary glands pull in more glucose without even needing insulin.  

The hormone prolactin, which is secreted from the pituitary gland and supports milk production, increases insulin sensitivity.   

Oxytocin, sometimes known as the love hormone, is also produced when breastfeeding. It lowers stress hormones, meaning less glucose is stored in the liver. This lowers your blood glucose levels and therefore your insulin requirements.  

Menstruation can return as early as six weeks postpartum even while breastfeeding, and may also affect insulin requirements, but this is very individual. 

Once your baby is eating solids and breastfeeding is tapering off, your milk supply will reduce, and insulin requirements will slowly increase to pre-pregnancy doses. 

Today, with improved technology including hybrid closed loop pump systems and CGMs, the challenges of breastfeeding can be much better managed.

With type 1 diabetes, anything is possible with the support of a credentialled diabetes educator and diabetes technology, so reach out to your health team.

Do you have any questions about diabetes?  

The Diabetes WA Helpline connects you with our knowledgeable diabetes educators, who are also qualified dietitians, midwives, nurses, pharmacists and exercise physiologists, to help you find the right support in one conversation.   

The Helpline is available from 8:30am to 4:30pm from Monday to Friday to answer all your diabetes questions – call 1300 001 880.