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This is part 2 of ‘How to Pump Breast Milk Efficiently’ series. In the previous article I’ve discuss things you should know even before start pumping. Now let’s move ahead and discuss about how to get correctly-fitted breast shield.
Do you know that getting a correctly-fitted breast shield is crucial if you pump breast milk?
Here are the reasons:
- Incorrect breast shield makes pumping uncomfortable (or in some cases, painful). This is especially true if you are using breast shield that is too small.
- Not optimal pumping output. With incorrectly size shield, you pump less milk. Yes, this is true. In my experience, getting correctly fitted breast shield may increase the pumping yield up to 20%.
So now, how to make sure you got the correct breast shield? In this article, I share my insights on how to choose properly fitted breast shield and my personal experience that proper fitting does matter a lot. Read further to know more.
(This is NOT a sponsored post. All products mentioned here were bought out of necessities . This post contains affiliate links)
There are a lot of guidelines and infographics about how to choose the correct breast shield, but my favorite is Medela breast shield sizing guide. It provides good illustration and great infographics. Maymom, on the other hand, provides FREE nipple caliper printable for download.
Medela mentioned to choose breast shield with inner diameter 4 mm more than your nipple diameter. Whereas Maymom mention 2-3 mm.
Personally I follow Medela guidelines in choosing my initial breast shield size, because it is simply clearer.
However, you should not follow this guideline blindly because the info graphic merely relies on nipple diameter only. In addition to nipple diameter, you should also consider the following factors:
- Check how your nipple moves while pumping.
The nipple should move freely and it should not rub the side wall of the flange. You may see a little bit of areola gets pulled, but not the whole areola. And your nipple should not hit the back wall of the breast shield.
- Comfort
Even if you think you already choose the best breast shield size, but you feel uncomfortable / painful while pumping, that means something is not right. Try to size up or down. Nipple redness / or sore feeling after pumping is also an alarm that you may need to choose different breast shield size.
- Effectiveness of pumping
If you feel you breast is not emptied after pumping, you may suspect that you don’t use the correct breast shield size (note: various factors can affect this, breast shield size is just one of possible reason).
- Breast tissue / elasticity
Some women has a very elastic tissue so that the skin will get pulled easier. In this case, it is possible that pumping makes nipple get elongated so much until it hits the back wall of the flange. For this case, using breast shield with longer ‘tunnel’, or using smaller insert in bigger breast shield may help.
- Suction preference matters
The stronger the suction you use during pumping, the more your nipple will be pulled into the tunnel. And there is higher chance to hit the back wall of the tunnel if you have quite elastic tissue. In this case, using ‘insert’ would be best approach to use.
IMPORTANT!
- Your left nipple diameter may not be the same with your right nipple diameter, and thus may require different breast shield size.
- Your nipple diameter may change (enlarge a little bit) during pumping session. I think that’s why Medela guidelines add extra 4 mm to determine your breast shield size from the actual nipple diameter. I think this ‘diameter’ refers to nipple diameter before pumping.
Are you struggling to pump enough milk?
This FREE pumping checklist summarizes my best pumping strategies that will help you pump effectively and get more milk!
Click here to download your pumping checklist
How I found my correct breast shield size
When I purchased my Medela breast pump, i refer to Medela guidelines to determine my correct breast shield size.
Based on nipple diameter alone, it would be the 21-mm size (size S). So in addition to the standard 24-mm shield (size M) I purchase the 21-mm one.
My mistake:
I didn’t compare from the beginning between using the two sizes. I used size S straight away, and use the maximum comfortable suction level I could.
Honestly, back then, I was not impressed by my Medela performance because it didn’t really empty my breast fully. But I thought that’s just how electric breast pump is.
One day, I decided to use the standard flange, and to my surprise, I got more milk. At that time I felt like dumb for not trying it from the very beginning.
I began using size M from that point onward, until I decided to try a new breast pump. Again, conversation with seller pointed me to the Medela guide again and I started wondering why this guide didn’t work for me.
My new pump had a flange diameter of 25 mm and I could feel that it was not extracting milk efficiently.
My nipple was constantly hitting the back wall of the flange. Not, it was not painful, but the suction become less efficient.
So I tried experimenting with different flange size, including attaching Medela 21-mm inside the original Spectra flange (yes, seriously I did that). And it works much better, but not so convenient.
So I searched for better option when I stumbled upon ‘breast shield insert‘. Aha, I think this is the one that I n
eed. So bought a pair from my local retailer and totally in love with it.
Here’s how it looks like. It says Medela 21-mm insert (NOT 21-mm breast shield, they are different!)
The advantage of using insert vs breast shield is you get a much longer tunnel length, so nipple won’t easily hit the back wall of the flanges even in highest suction setting.
And you know what? Once I switch to using my new ‘breast shield system’, which essentially using a 21-mm insert inside a standard breast shield, my pumping yield increases up to 20%. Whoaa… I wish I figured this out much earlier..
So, again, I strongly recommend you to compare several breast shield size right at the beginning, especially if you have not found a good fit with the standard size that comes with the pump.
If your pump does not come with a variety of breast shield size, do try Maymom breast shields. Maymom is not breast pump brand, but it offers compatible breast shield of various sizes for Medela, Ameda, and Spectra.
For Medela-compatible breast shields, it has 11 different sizes: 15, 17, 19, 21, 24, 25, 27, 29, 30, 34,36 mm, and additionally 22-mm insert (to be used with 25-mm flange) and 28-mm insert (to be used with 30-mm flange). Quite a whole lot of variety to choose from.
Other moms’ stories
Now that you’ve heard my story, I wanted to share some of my readers’ story who managed to avoid pain while pumping and have increased their pumping output by using the correctly-fitted breast shield.
Aida has recently shared her success on increasing her pumping output after switching to a smaller breast shield.
Here’s what she said:
It’s really true! Correct flange size will give better output. My first baby is almost 3 months. I have no deep knowledge about breast milk since this is my first baby.
I really dig the info because I
wonder how other people can make it, how to breastfeed my baby till 2 years if everytime I pump I feel pain and sore. Then only I know how to measure my nipple and choose the right flange size.
From flange size of 28 mm, I changed to 24 mm, and now 21 mm. It really hurts when I pump using 28mm breast shield because it also pulls quite big range of my alveolar. Now, no more pain.
.
(look at the pic) After 20mins pumping, my baby woke up. I direct fed my baby and continued to pump the other side to complete 30mins. Before this most yield is 3 oz each side. Thats the max, normally it is less than that, hahaha.
FYI, I’m using Spectra and Maymom 21-mm breast shield.
wonder how other people can make it, how to breastfeed my baby till 2 years if everytime I pump I feel pain and sore. Then only I know how to measure my nipple and choose the right flange size. 
Rina’s comment: from 3 oz each side to 3.5 – 4.8 oz, wow.. that’s a huge increase, congrats, Aida.
Another reader, Linda, shared that after using the 21-mm insert, she managed to increase her pumping output.
I just bought “Medela breast shield 21-mm insert.” It fits Spectra 24-mm flange too, or if you use Medela, fits in 24-mm flange. I’m using both. I also used hospital grade Spectra breast pump (i.e Spectra S1). Guess what? My output is 150% up (compared to my yield when I pumped for my first born)!
So, if you haven’t tried to really measure your correct breast shield diameter, you should do this. Correctly-fit breast shield leads to more milk, proven!
Now, if you have tried several sizes and you feel that your pumping yield is not optimal, or the way your nipple moves back and forth does not feel comfortable, you may try using Pumpin Pals flange.
June shared that she experienced nipple pain and ‘hitting the back wall’ problem with her original flange size.
Well, I tried both the 30-mm and 24-mm Maymom breast shield and one too large while the other too small. So my original size of 27-28-mm is correct, just that my tissue is elastic.In the end I bought Pumpin pals and that seemed to solve the problem of hitting the back wall.
::
Now, let’s summarize what we learned here.
To choose the correct breast shield size, there are a few things to consider:
- Nipple diameter (follow Medela guidelines)
- Comfort (discomfort means something wrong)
- Suction preference (higher suction: may need longer breast shield tunnel)
- Breast tissue elasticity (more elastic: longer breast shield tunnel)
- Effectiveness of pumping (more milk with correct breast shield size)
If you feel that your breast pump brand does not cover a wide-variety of breast shield sizes, here’s some recommended accessories that may help:
- Maymom breast shield: covering breast shield diameter from 15-36 mm (plus 22-mm and 28-mm inserts)
- Pumpin Pals super shield: 3-size angled breast shield that promotes pain-free pumping and no need to leaning forward while pumping.
I hope this article will help you to pick the correct breast shield size, and thus, able to pump more effectively.
If you have any questions, feel free to ask. I’m glad to help.
Now, my question to you: Have you tried various size of breast shields and picked the correct one for you? How was it? Do you think using correct breast shield can maximise your pumping output? Share your insights with us!
Are you struggling to pump enough milk?
This FREE pumping checklist summarizes my best pumping strategies that will help you pump effectively and get more milk!
Click here to download your pumping checklist
Thank you so much for this article. I am distressed as I can’t figure out the correct flange size for myself. I use the Spectra S1 with a Spectra 28mm flange. My nipple rubs against the sides while pumping which would suggest that flange is too small. But at the same time my nipple hits the back wall of the flange and a lot of my areola is drawn into the flange – this would suggest the flange is too big? I have tried the larger 32mm Spectra flange but the problem of hitting the back wall of the flange remains. What would you suggest in my case? You mentioned using flanges with longer tunnels or inserts- which brands have longer tunnels and which brands have inserts? Many thanks in advance!
Hi JL,
Have you tried measuring your nipple diameter? How much is it?
Hm.. I am a bit confused with your explanation.
If your nipple is rubbing against the side wall, there’s no way your areola will be drawn into the flange. Is it maybe your areola which rubs against the side wall?
Since you mentioned your areola is drawn a lot inside the 28-mm flange (and nipple hitting the back wall), it seems to me that the 28-mm flange is too big for you.
I suggest you try the smaller size (25-mm flange), and see if your areola is still drawn a lot inside and your nipple still hits the back wall.
You asked which brand has longer tunnel diameter and insert => It’s Maymom.
The 30-mm flange especially has much longer tunnel compared to other brand.
It has 22-mm insert (to be used in 25-mm flange) and 28-mm insert (to be used in 30-mm flange).
If you decide to try Maymom brand, you can use a simple hack to connect it to your Spectra pump (search: “spectra hack “in my blog’s search bar).
Let me know if you manage to solve your problem, and feel free to contact me again if you have further question.
Cheers,
Rina
I am having the exact same problem. Nipple rubbing against the side and hitting the back wall. Plus the spectra empties my left breast but not my right. When I go down in size the friction against my nipples is too painful. I am about to give up!
Hi Tee,
If your nipple is rubbing against the side, that’s definitely too small.
Have you tried going one size up? Or use PumpinPal?
Also, if you have trouble emptying your breast, I’d strongly recommend massage while pumping and follow up your regular pumping with hand-expression / manual pumping. This is the only way I can empty my breast thoroughly.
Hello
I think that you have a wonderful site and so much information but it took me a lot of searching to find how to leave a comment but glad that I was able to find it
I think you will do even better in your second year
best regards
paul
Hey Paul,
Thank you for taking your time to visit my website and leave a comment.
I really appreciate it.
Thanks for your compliment and I continue trying to write better articles to serve my readers.
All the best for you, too
Rina
Thank you for this post. I’m wondering if you can offer any insight into my situation. My daughter is in the NICU still – born at 29 weeks. So I’ve been exclusively pumping since her arrival. But I’m not expressing enough to avoid any supplementation at this point. I asked lactation about the flange sizes early on because I wasn’t getting much milk and thought too much aereola was being pulled in. That sounded like the size was too big to me – but she told me I needed bigger. So with the bigger, I got more milk out, but I never feel drained (and I’ve already had mastitis). I measure 17 mm and am using a 33 mm on the Ameda Platinum. A lot is pulled in and everything starts going sideways as I increase suction. So the nipple rubs a bit with each pull, but only on one side because I’m going diagonal. Any thoughts?
Hi,
17 mm is your nipple diameter but you use 33 mm? That sounds too big.
I suppose you have tried the standard 25 mm of Ameda and not getting enough milk.
Have you tried going one size down (21 mm) or perhaps use 21 mm insert?
If you read my story, I ended up using 21 mm insert in 24 mm flange (21 mm is my actual size, but when i tried only 21 mm flange, the funnel is too short hence painful and thus I use 24 mm).
Also, a lot of moms have great result using pumpin pals, so you may try if pumpin pals suits you better (the package has three sizes so you can try each of them and see which size fits you better).
Aside from breast shield sizing, I suggest you to do hands-on pumping, i.e. massage your breast while pumping, finish up with hand-expression / hand-pumping, also try if you can get the second let-down. I know, this means more work for you, but I highly recommend to try these methods as it will definitely help you to thoroughly empty your breast and therefore, prevent mastitis.
I don’t know if you’ve read this article:http://livingwithlowmilksupply.com/how-to-pump-more-breast-milk, but basically it gives you more explanation about what I mentioned about hands-on pumping.
Btw, the lactation consultant you saw, is she an IBCLC? IBCLC has a lot more experience (1000+ hours of helping moms in breastfeeding and all) and thus, can give you better suggestions.
All the best,
Rina
Hi Rina,
My nipple diameter is 17mm so should i buy Pumpin pad set large or set small?
Thanks a lot,
Hien
Hi Hien, small set.
Thank you for the sharing. My nipple is not round. It’s abit like ovul. So how should I measure? Should I take the largest diameter or smallest?
Hi,
To be honest, I don’t know. Perhaps *okay, this is just perhaps* you can try the largest, because we want to avoid the nipple rubbing with the flange’s side wall, right. Does this make sense?
Measuring your nipple is just the first step. You still need to try the ‘new flange’ based on your measurement and see if your pumping becomes more comfortable.
Hope this helps.
Rina
currently using spectra 9+ and is a working mum. i using the maymom measurement and it supposed to be 19mm.. but i get 21mm instead. when i pump, it is more comfortable but.. seems the milk always gather at the breastshield area and i cant get it clear well.
so i used back the spectra standard 28mm.. and it can express more milk.. however, because it can move freely inside.. lesser chance for the milk gather at the breastshield area . normally i will pump 30 mins at work and hand express afterwards. but it seems after 20 mins, then my nipple getting longer and will hit the wall.
once completed the 30mins session, normally i will hand express for a short while… sometimes i can feel some small lumps near the nipple area and hand express can clear it much better. should i continue to pump after hand express? and one of mine is inverted.. it is really hard to hand express and is the one always hit the wall…
how to clear it better and pump more efficiently. need your advice. thanks!
Hi Ivy,
My suggestion is to choose which one you feel more comfortable and more convenient. Does it concern you when it hits the wall? Any pain/ discomfort, etc? Because for me personally, even though there’s no pain, I felt that my breast was not emptied fully when that happened, so that’s why I choose to use other breast shield size.
Also, try to massage your breast while pumping, it will clear out milk faster.
Regarding your question, should you continue to pump after hand-express? That depends. Have you tried second let-down? This is how I do mine: get first let-down, double pump until flow slows down or no milk come out, hand-pumping (to replace hand expression), then second let-down, double pump, hand-pump, and so on. For me, getting 3 let-downs is optimal, but I know for every woman is different. You need to experiment here, there’s no universal rule for all.
Hope this helps,
rina
Also, have you tried the breast shield insert? it’s a little ‘cone’ that you can put inside the bigger breast shield size, so that your nipple can move further, but you can still restrict your areola from being pulled too much.
hi rina,
i am a new mum to a two month old girl. i was those preggies that took it for granted my milk will overflow once the baby is out, sadly aft a stressful emergency c-sec the milk only came about the third day and very minimal.
so i sent my husband out on a quest for a breast pump during my confinement period and he got me a bumble bee breastpump
in the beginning it was fine as i was having my girl direct latch more often. (we are supplementing her w FM btwy), BUT now she pushes the bottle away, prefers the breast!!
so i started pumping more, but the nipple and aerola hurt so bad after the sessions! after reading your blog, i realised my flange size was too big for me!
i t is 24mm with the silicone inserted. i would like to get myself a spectra S1 to do some serious pumping for my girl. can a 21mm shield insert from medela be used for spectra? and where did you find your shield insert in malaysia?
thank you
If you mean 21-mm insert inside Spectra 28-mm shield, no it won’t work. Theoretically it can still be inserted, but since the insert is smaller than 28-mm ‘tunnel’, the insert will move as the suction cycles.
So, you need a 24-mm breast shield. I haven’t tried with Spectra 24-mm shield since I already have 24-mm medela, I just used that one.
I’m not sure where you can get the insert in Malaysia, but I know several malaysian mums ordered from Kulily.com and bingbling (both singapore-based) collectively. I got mine from bingbling since it eas near my office.
hope this helps.
Hello! Thank you for sharing good articles!
It is my second baby so I am reading to refresh myself on how to pump.
Can you recommend any breastshield for Avent pump?
Also, what is the average milk output for the first let down?
Thanks!
Avent Comfort has fixed-size breast shield, but it has 2 sizes for the breast shield cushion (normal: 25 mm, large: around 28-mm).
I’m not sure if you are refering to the new model (Avent Comfort) or old model (Avent classic).
If you are using Avent Classic, I believe you can put pumpin pals flange there. Not sure with the comfort one.
For average milk output for the first let down, it will be different across moms. There’s no average I think
Hi Rina, thank you so much for all the information stated here. For various reason, unfortunately i could not direct feed my 7 week son and has been exclusively pumping (on occassion i did attempt to direct feed but didnt work out for us both). So I’m pumping every 2-3 hours now and only could yield about 1.5-2 oz from both breast combined. After each 20 minutes session of pumping i feel sore. Im using Lacte Duet and Autumzn Bliss pump. I seriously have no idea how to make sure that i have picked up the correct pump and now felt that the pumps are not suitable. I had breast surgery before (3 times both side, for fibroid) and taking all iniatives to boost my supply but there were no improvement. You did mentioned about blood test and breast examination, where can i do such test? Thank you
Hi Nur Hidayah, you can contact a local IBCLC, explain your condition and ask them to do the test. I suggest you to join FB group: IGT and low milk supply support group and look at the ‘files’ to see the detailed test (esp blood test one).
Also, since you have breast surgery in the past, this post may help.
All the best, and I’d like to remind you, even if you cannot provide full milk supply for your child, that 1.5-2 oz is precious for him. Don’t give up, ya.. =)
Hello! Thank you so much for your article. I have been using the Spectra pump 28mm breastshield for 6 months to pump for my 10 month old daughter while I work full-time. All of the sudden my milk supply has plummeted. I have noticed that my nipple is being pulled and hitting the back wall as you described. I cannot seem to find a clear fix for this and I am very concerned about my supply. Can I get an insert for the Spectra pump even though it is says it’s a Medela insert? So confused with the million different hacks!!!!!
Hi Marie,
Not sure which insert size you are talking about. I did try 21-mm insert inside 28-mm Spectra and it’s not working.
Hi Rina, I am currently using spectra S1 pump with 19mm breast shield. I have tried 28mm, 24mm and 21 mm and now 19mm but all of these pull my areola , lesser with 19mm. But now the smaller breast shield is causing abrasion to my areola, so the pulled part is red and shiny now. After pumping for awhile, I can see that parts my nipple rub against the wall but now much. I am not sure what else I can do. Should I try 21mm again when more areola is being pulled? My right areola is worst than left.
Hm.. that’s confusing, what setting do you use?
And among them, which one feels most comfortable and yield most milk for you?
Why don’t you try contacting Pumpables fitting room. They can help you with the breast shield fitting.
I am using massage mode – 70 cycle speed and level 4 suction, then change to expression mode- 50 cycle speed and suction level 6. Both 21 and 19 mm pulled my areola but I am not sure what is acceptable. The based of my nipples/areola are red and shiny due to the constant pulling and abrrassion.
The setting you are using looks fine, not too high.
I would choose the one gives you most comfort and more milk.
If only part of Areola going in, that’s ok, as Long as not too much and no pain.
Have you tried lubricate your breast shield with some lubricant (eg coconut oil)? Some moms say this helps with pumping discomfort.
HI Rina, glad i chanced upon your post, its really informative.
Im currently doing exclusive pumping using medela freestyle pump. Bought their highest range as i wanted to continue pumping when I head back to work.
But i have large nipples and the usual 24mm does not fit me.. tried 27mm but the nipple movement during pumping is up and down so it still rub against the funnel.
both nipple size measured is 22-23mm
so i changed to 30mm flange.. alot of my aerola is being pulled in.. its painful but still lesser than my nipple being rubbed against the wall.when using 27th. but its getting more and more painful..
any advice? I went to a Lactation consultant and she told me theres no sheild for in between sizes.. Sigh
bought pumping pals M size but it rub against the funnel too..
Hope u can provide some advice..thank u in advance.
If I were you, I would choose the one which is more comfortable and give most output between 27 and 30 mm. Oh, I noticed that Maymom carry a 28-mm insert that can be used with 30 mm shield. Perhaps can try that one?
Another suggestion: try to talk to someone in Pumpables (search Pumpables fitting room).
Good luck!
Hi, I am using spectra flange 28mm and milk output is imbalance where right breast yield 100percent more than left breast, and today I tried medela 24mm and both breast yield the same. Should I change my spectra flange into 24mm in order to draw milk more efficiently ?thanks
I would choose the one gives me more comfort and more milk.
The imbalance is pretty normal actually.
Hi. Do you noe where can i get pumpin pals super shields in sg, msia or even brunei? I have been struggling to find the corect flanges for myself.. Been having cracked nipples since day 1 despite i changed a lot of flanges.. Soft n hard flanges n even use neaugen cushions n still i get sore nipples.. So i desperately wanted to try pumpin pals.. But i dono wer can i get them
Hi,
In Singapore, you can get those in Kulily or Pupsik Studio.
I’m not sure about Malaysia and Brunei. But if you can’t find it locally, you can try buying it directly from Amazon and use freight forwarding service such as Borderlinx.
Hi rina. I’m a new mom for my first child, so dont have much knowledge about breastfeeding.
In about 2 weeks, i’ll back to work and currently working to stock up my milk supply for my daughter while i’m working, and i found out when i pump my breast, it still not emptied my breast effectively, my breast fit the wall of funnel and sometimes feel pain when pumping. suspect maybe funnel size is too big with my breast. however, currently i’m using lacte duet breast pump and their funnel size was standard (24mm). can i use maymom insert to my lacte duet silicone funnel to size down in order to get the correct fit to my nipple size?
Hi dear,
I haven’t tried Lacte personally so I don’t know whether Maymom insert would fit into its flange. For an alternative, you can also look at the Maymom flange insert for Freemie (available in various sizes). Originally, this was supposed to be used with Freemie cups, but a lot of moms use it with regular breast shield too. Unlike the Maymom insert that I mentioned in this post, this insert is silicone-based so it feels softer.