By Vitali Charapovich

Breast Pump Flange Guide

choosing the right breast pump flange

Written by Jade | Midwife, Mama of 3 & Tiny Hearts Educator

Want to know one of the things they don't tell you about when it comes to pumping breastmilk? There are many different size flanges, and using the wrong size can impact upon the amount of milk you get + any discomfort you feel while expressing. Read on for how to choose the right size for you and more tips + tricks for expressing breastmilk. 

 And FYI, for any mamas that are new to expressing, the flange [sometimes known as a breast shield] is the plastic part of the pump that you hold against your boobs and place your nipple into. The pump creates a seal around the areola and nipple within the flange to suck and release the nipple, similar to the rhythmic sucking of a baby at the breast. 

choosing the right flange size

When choosing the size of your breast pump flange, you need to consider the size of your nipple and the level of comfort you feel when you are using it to express. Most breast pumps come with a 'standard' size flange but will offer smaller or bigger sizes too. Flanges often come sized in millimetres [mm]. The mm size of the flange refers to the width of the opening. To work out the flange you need, measure the diameter of your nipple: 

1. Use a tape measure or ruler to measure from one side of the widest part of your nipple to the other, which is usually across the centre [don't include your areola- nipple only] 

2. As a general rule, add 4mm, and that's the size of the flange you should choose 

 Remember that throughout your postpartum and breastfeeding journey, you may need to go up or down sizes, so continue to monitor the size, fit + feel of the flange and the effectiveness of your pumping in case you need to go up or down a size. Some mamas even find they need a different size flange for each breast.ore.

signs your flange is the right size

- You can express comfortably [may be uncomfortable at first while drawing out the nipples, but this settles] 

- Milk doesn't leak out the bottom of the flange 

- Your nipple fits comfortably in the centre of the flange 

- Your nipple moves freely [note: your nipple can touch the sides of the flange as long as it doesn't restrict the movement]

signs you may need to go down a size

- Your breasts still feel full after expressing 

- Milk leaks from the bottom of the flange 

- There's a lot of room between the nipple and the sides of the flange 

- You have a slow letdown in comparison to when breastfeeding 

- Nipple swelling while expressing 

- Breast tissue is being pulled into the flange instead of just your nipple

signs you need to go up a size

- Pain when expressing 

- The nipple feels very sore after expressing 

- Reduced milk flow 

- Then nipple's movement is restricted by the flange 

- The area around the nipple turns red or white during or after expressing

Get the perfect fit 

cleaning your expressing parts

If bub is healthy and born at full term, you don't need to disinfect or sterilise your flange and expressing parts after each feed. Instead, you need to rinse it well in cold water after each use and store it in a clean, sealed container. If you've got a fridge, you can store it unrinsed in there inside a clean, sealed container. Once every 24 hours, the flange and other expressing equipment should be cleaned using hot, soapy water and left to air dry. But if you're only using it to pump once a day [or less], clean it thoroughly using hot, soapy water after each use. 

expressed breastmilk storage

The Australian Breastfeeding Association [ABA] tells us that freshly expressed breastmilk expires: 

 - After 6-8 hours at room temp 

 - After 72 hours in the fridge 

- After 2 weeks in the freezer part inside a fridge 

- After 3 months inside a separate freezer attached to a fridge 

- After 6-12 months in a deep freezer 

 Breastmilk that has been frozen, then defrosted in a fridge but not yet warmed expires: - After 4 hours at room temp 

- After 24 hours in the fridge 

 Breastmilk that has been defrosted outside the fridge in warm water expires: 

- Once bub has finished feeding from it 

- In the fridge for 4 hours or until the next feed 

If breastmilk has been defrosted, warmed, and bub has started feeding from it, it's recommended to be discarded once bub has finished feeding. 

 In all of those cases, you might be left with expired breastmilk you can't feed to bub. Here are some ideas of what you can do with it instead of pouring it down the drain: 

- Milk bath. Pour your milk into bub's bathwater; great for little skin. 

- Make it into soap. There are lots of recipes online for you to follow to create soap out of breastmilk.  

- Mix with water and spray onto cradle cap to help soften it.  

- Make it into body cream/ moisturiser. Again, lots of recipes online for you to follow.   

- Send it off to be made into jewellery. I've seen some absolutely stunning pieces of jewellery made of breastmilk, like rings and pendants for necklaces. Some mamas also say it acts as a keepsake from their breastfeeding journey too.  

rusty pipe syndrome

 If you're a mama who has expressed before, and your colostrum or breastmilk appeared pink, brown, or blood-stained, you may have heard of this before. 

 Rusty pipe syndrome occurs in the first few days after birthing your bub. It's thought to be caused by the growth of your milk ducts and milk-making breast cells. Generally, it doesn't occur after seven days. So if you see blood-stained breast milk after this point, it's likely caused by nipple damage, cracks and bleeding or, less commonly, caused by benign wart-like growths in the lining of milk ducts, so follow up with your Midwife, Lactation Consultant [LC] or GP. 

 The true rate at which Rusty pipe syndrome occurs isn't known because if a mama is breastfeeding directly and doesn't express, they may not know the colour of their breastmilk. While it may look alarming, Rusty Pipe Syndrome is normal, and you can still feed your expressed breastmilk to bub, unless otherwise advised by your or bub's healthcare team. Some mamas may struggle with the psychological component of feeding bub breastmilk that appears discoloured, and in this case, I'd encourage you to chat with your Midwife or a LC before stopping breastfeeding based solely on this reason.  

High Lipase in Expressed Breastmilk

 Does bub refuse to drink your stored or defrosted breastmilk? Does your stored or defrosted breastmilk smell or taste soapy?  

 If yes, it could be due to a high lipase level. Lipase is an enzyme that occurs naturally in breastmilk that breaks down fat into fatty acids. Lipase in breastmilk is completely normal and isn't harmful, but high levels of lipase can give the breastmilk a different smell and taste, which is often described as soap-like. Some bubs may drink it; however, many refuse it too.  

 Each mama produces a different amount of lipase. Unfortunately, there's nothing you can do, eat or take to change the amount of lipase you produce in breastmilk. Some mamas with high lipase try to prevent the taste and smell from changing by scalding their breastmilk shortly after expressing it before putting it in the freezer. This is thought to slow down or stop the lipase from breaking down the fat in the milk.  

 To scald the breastmilk, Spectra recommends placing the freshly expressed breastmilk into a pan over medium heat and warming it up to 82 degrees Celcius. Once you reach this temp, cool it [often in an ice bath] and place it into your storage bag and freeze. Alternatively, some mamas place the milk in the bottle in a bottle warmer, and warm it there, then cool and freeze in a storage bag. Regardless of which method you choose, be careful not to boil the milk, and avoid holding bub while doing this to minimise the risk of burns.  

 If you've got a freezer stash of breastmilk with high lipase that your bub won't take, consider donating it. While your bub may refuse it, some others may take it. Otherwise, you can use it in milk baths, added to purees, or when baking bub's snacks.

 For more info and tips and tricks from a Midwife on expressing, breastfeeding + formula feeding, check out our Online Birthing course, linked below.   In the meantime, head back to the original post and let me know in the comments, did you express breastmilk for your bub and how long did you pump for? 

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