Size does matter....but bigger is not always better

Let’s talk flange sizing – it is something that could make or break your expressing journey.


My personal experience with using the wrong sizes

I was told to start expressing by an IBCLC for my daughter when she was 3 days old. My milk hadn’t come in and it looked like she had lost too much weight. I was initially told that I needed 27mm flanges. A week later I went for a follow up appointment and was told that I needed 30mm flanges because I wasn't expressing much. Having very little expressing knowledge I believed them (this was despite working in NICU for 8 years already - it certainly wasn't something we learnt much about).


By ~10days post birth I was barely expressing 10-20mls/session. Slowly it increased to about 30mls/session but would not increase any further. Using the 30mm flanges hurt and I kept going back to the 24mm flanges that I had as they were slightly more comfortable. I would also get more out (only about 10mls more and no more than 30mls total).


Around 6 weeks post birth I saw a different IBCLC who wanted to help me increase my supply and suggested I try a different brand of breast pump while I waited for my Spectra to arrive. And she suggested that I try 36mm flanges. In between all this, another IBCLC had agreed that 30mm flanges seemed to be correct.


I tried the 36mm flanges but quickly went back to the 24mm’s – they were definitely more comfortable and I got more with them. Although it definitely was painful to express I pushed through, wanting to give my daughter whatever breast milk I could get.


About 2 weeks before I ordered my Spectra I tried a friends electric pump (a brand that you can buy off the shelves in Big W or Target) which had ‘comfort massaging inserts'. I got the most I had ever got – 40mls! When another friend told me about the Spectra I ordered it with their ‘massaging inserts’.


I also joined an Exclusive Expressing / Pumping Facebook group on her recommendation. After a week or so I posted my story, desperately wanting to increase my supply. The main thing I was told was to increase the number of sessions I was doing (I was only doing 6/day whereas the minimum is 8). But someone in there also recommended checking my flange size. I didn’t pay too much notice to that suggestion as I was now using the Spectra 24mm’s with the inserts (which took them down to a 22mm) and it was somewhat comfortable and I was seeing an increase.


Over the next 8mths of exclusive expressing (I did my last session 3 days before my daughter was 10mths old) I saw numerous posts about flange sizing. And I came to realise just how important it was to get the correct size and that unfortunately those 3 IBCLC’s who had told me I was a 30-36mm were wrong.


“Your flange should fit your nipple like a shoe”

Professional experience with flange sizing

In March 2016 I started selling Spectra breast pumps as an authorized stockist. Flange sizing quickly became a ‘passion’ of mine (some might say obsession!). I realized that so many new mothers were being told the same thing as me – you need a 27, 30 or 36mm flange.


I started stocking Maymom flanges around the same time as the Spectra breast pumps and I did a survey on the Exclusive Expressing group to work out what volume of stock I should be ordering. Most said they were between a 19 and 27mm flange, so that is mainly what I stocked. Over time I realised I was selling more 19mm’s than anything else and I was getting numerous requests for 17's and 15’s.


A fellow IBCLC from the USA, who I know went through similar expressing journey to me (she is in the Exclusive Expressing group), did a similar survey to me just recently and interestingly the vast majority said they were a 17, 19 or 21mm.


Results of the informal Facebook survey done by a fellow IBCLC. This is a screenshot taken from