Finding your nursing bra size can feel a little confusing, particularly when you're pregnant and your body is changing.
Your usual bra size may no longer feel right, but you also don't know exactly what size you'll need once your baby arrives.
The good news is that you don't need to overthink it.
The most important thing is finding a nursing bra that feels comfortable, supportive and secure.
Start by measuring yourself
If you're buying a new nursing bra, start with an up-to-date measurement rather than automatically buying the same size you've always worn.
You'll usually need two measurements:
Your underbust measurement — taken around your ribcage, directly underneath your breasts.
Your bust measurement — taken around the fullest part of your breasts.
These measurements can then be used alongside the individual brand's size guide.
And that's important because bra sizing isn't completely standardised between brands.
Always check the size guide for the particular nursing bra you're buying.
Don't rely on the size you wore before pregnancy
It can be tempting to simply order your old bra size, but pregnancy can change your breasts and your ribcage.
You may need a different size or even a different style.
Rather than worrying about what your "normal" size used to be, concentrate on how the bra fits now.
How should the band feel?
The band should feel secure around your ribcage without digging in or feeling uncomfortably tight.
It should sit fairly level around your body rather than riding up at the back.
If you're constantly pulling it down or tightening the straps to get enough support, the size or style may not be right.
How should the cups fit?
Your breasts should sit comfortably inside the cups without obvious spilling or bulging.
The cups shouldn't dig into your breast tissue, but you also don't want large amounts of empty space.
Some nursing bras have more flexible cups than traditional bras, which can be particularly useful when your breast size changes throughout the day.
What about sizing during pregnancy?
This is where things get tricky.
Your breasts can continue changing throughout pregnancy and after your baby arrives, so there's no way to guarantee exactly what size you'll be later.
Rather than buying lots of bras several months before your due date, it can make sense to buy a couple at a time and see how your body changes.
If you're buying a nursing bra towards the end of pregnancy, look for a style that offers some flexibility.
What if I'm between sizes?
If you're between sizes, don't automatically choose the smaller one.
Comfort and support are much more important than squeezing yourself into a particular size.
Check the manufacturer's size guide and consider the style of the bra too. A flexible nursing bra may fit differently from a more structured style.
If you're unsure, a professional bra fitting can also be really helpful.
Remember: the label isn't the most important thing
A 34F in one brand might not feel exactly the same as a 34F in another.
That's why the best nursing bra isn't necessarily the one with the "right" number and letter on the label.
It's the one that fits your body comfortably and gives you the support you need.
If you're still unsure about what a good nursing bra fit should feel like, take a look at our How Should a Nursing Bra Fit? guide.
Looking for a nursing bra?
Explore our collection of nursing bras and find a style that's comfortable, supportive and designed to make breastfeeding easier.