Bras 101: The Ultimate Mom’s Guide to Bras That Fit Right (During Pregnancy & After Babies)

I know what you’re thinking… “Girl, please. I do not need to talk about my boobs. I do not need a reminder that they aren’t what they used to be before my babies.”

Well prepare to be amazed, my friends! Your opinion about your breasts is about to be resurrected. I am about to reveal to you the mystery of a perfect (or, at least close-to-perfect) fitting bra.

What? You don’t believe me? A couple weeks ago I’m not sure I’d believe me either. But, as it turns out, the secret is not this crazy, hard-to-understand cipher. It does take a little measuring and calculating, but with some basic info I promise I can make this easy as pie!

What do you think? You ready to conquer with me? Let’s go!

A properly fitting bra helps you look better in the clothes you own. One big key to avoiding a frumpy look is making sure your breasts are properly supported under your clothes. When they are, you’ll look instantly slimmer and your clothes will fit better.

The Facts About Bras for Moms (+ Support)

When you are wearing a bra that fits correctly the band will carry 80% of the weight and the straps the other 20%. Wearing a bra is helpful for so many things, but especially when it fits correctly. There are many perks to wearing a quality undergarment:

• Controls sweating

• Hides nipples

• Delays sagging (helps ligaments keep elasticity longer)

• Prevents bouncing (aka PAIN) during workouts and activity

• Clothes fit better

• Adds insulation

• Reduces friction

• Helps with posture

• Prevents back pain

A study done in 2008 showed that 80% of women wear the wrong size bra. 70% were wearing bras that were too SMALL. And the other 10% were wearing bras that were too big.

If that doesn’t peak your interest here are some signs you could be wearing the wrong size:

• Your breasts overflow the cups on the top and/or sides (creating additional “side boobs” or “quadraboobs”)

• The band rides up your back or isn’t parallel to the floor

• You get red marks on your shoulders from the straps

• You get read marks under your breasts from the underwire

• Straps fall down

• Cups are wrinkling

• Gore (center of the bra where the cups meet) is not flat to your chest

I think it’s a given most of us want the qualities in the first list and don’t want to deal with the issues in the second. I promise that we can do that and you don’t have to sell your soul to get them.

What the Different Parts of the Bra Are Called

Let’s get acquainted with the anatomy of a bra as we’ll be using some of these terms in this post:

The Correct Fit on Bras During & After Babies (+ the low down on cup sizes)

When you are wearing a properly fitting bra:

• your band should be parallel to the floor and you should be able to fit two fingers under your bra strap (at the shoulder, one finger stacked on top of the other).

• If your bra has underwire, it should curve up the sides pointing to the middle of your underarm.

• The center gore should be flat against your chest and you should be able to lift your arms and your bra stay firmly in place.

How To Put Your Bra On Correctly: The Scoop-and-Swoop

Whether you are convinced your bra fits or doesn’t yet, I want you to all follow along with this quick lesson on how to put your bra on. Don’t roll your eyes at me (even though I know you want to). I’m totally serious. This may change your life from here on out. Ready?

1. Put your bra on, band first, by wrapping around your body and fastening the hook-and-eye closures.

2. You can choose to put your straps on now or at the end.

3. This is the important part! Lean over so your chest is facing the floor and scoop all your breast tissue (you may want to do a quick massage by swiping your hand under your arm towards your chest to grab any migrated tissue) and swoop your breast into the cup. You want ALL breast tissue in the cup. Not to the side under your arm. Not where your band sits. Not below your band. In the cup! This is called the Scoop-and-Swoop!

4. You can choose to put your straps on now if you haven’t already.

5. Now stand up and look in the mirror. I can guarantee that those 70% of you who are wearing cups too small are now also convinced of that truth.

How Your Bra Should Fit: Video

Here’s a quick video I found that demonstrates the points above. If your bra doesn’t fit based on this method or doesn’t fit based on any of the requirements in the paragraph above, you need a different bra. This could mean you need a different size or maybe just a bra that is better designed for your shape.

Keep reading and I’ll help you figure out which it is.

Breast Shape:

Certain bras are better for certain shapes?

Don’t get annoyed with me, but yes. There are many different breast shapes and while most of us probably fit the majority of bra styles, some don’t. I’m not going to delve too deep into this otherwise we’d be here all week, but here are the basics if you think this might be you.

Be aware if you have lots of breast tissue in a certain side/top/bottom of your breasts. You can usually tell this based on where your nipple is on your breast and where it naturally points.

If you imagine your nipple being the center point of your breast you should be able to see if you have more tissue below, on top or on one side. You may have more fullness at the top of your breasts and you’ll want to be wary of bras cutting into your breasts at the top of the cup and creating another “boob” above your cup (gasp! we don’t need more!).

OR you may have more fullness at the bottom and less at the top so you’ll want to be careful that your bra has a larger arc at the base and isn’t too big at the top where you won’t fill it out.

If you want to delve into lots of details, there are some great resources here and here, including some specific bras that work best for certain shapes.

Cup Sizing:

You know the phrase or joke you hear that assumes someone who is a DD cup means they are supremely well endowed? I’m here to tell you that statement holds no weight (haha? bad joke? ok, I’ll move on). Did you know that not all D cups are the same? A 32D cup is not the same as a 38D cup.

Your cup size doesn’t equal the size of your breasts. *gasp!* Let me say it again. Your cup size is NOT the size of your breasts.

The cup size refers to the difference between the size of your breasts and your rib cage.

The larger the band size the larger the cup. So if you wear a 34C and feel like your band is too tight going up to a 36C will also mean you just went up a cup size. Here’s a quick graphic to show you what I mean.

The top row shows 5 different bra sizes that have same cup volume (these are called “sister sizes”). The second row shows five sizes of DD cups and there you can see that the larger the band, the larger the cup. The last row shows bras with the same band size and how the cup sizes go up.

Here’s another chart that shows what your “sister size” might be.

This isn’t rocket science, but it’s important to understand if you want to find a bra that fits you correctly.

Finding YOUR Perfect Bra Fit

Let’s do some quick measuring (less than 5 minutes, I promise). It’s easiest if you do it in front of a mirror so you can make sure you have your tape measure straight across your back.

#1 How to Find Your Band Size Measurement

1. Remove all clothing from the waist up, including your bra.

2. Using a soft measuring tape, measure around your torso, directly below the root of your breasts. This may feel lower or higher than you expect, but it’s important that your measurement does not include breast tissue.

3. Exhale, then pull the measuring tape so that it’s very snug, but not so snug you are leaving red marks. Make sure your tape is straight all the way around your back (thanks, mirror!).

4. Write down this number.

#2 How to Find Your Cup Size Measurement

1. Lean forward so that your back is parallel to the floor and gravity is pulling everything down (bear with me, it’ll be worth it). Reach to each side and massage under your arm in a downward sweeping motion so that any migrated breast tissue is moved forward from your underarm to where it should be.

2. Using your soft measuring tape, wrap it loosely around your back and breasts, pulling just snug enough so that the tape doesn’t slip off your skin easily, but not so much that it pulls your breasts in. Again, check in the mirror to make sure your tape is straight across your back and around the front.

3. Write down this number.

How to Calculate Your Bra Size From These Measurements

1. Round your band size (first number) to the nearest whole number. Round up for a comfort fit and round down for a snug fit. If an odd number add 1″. This is your band size.

2. Subtract your under-bust measurement (first number, but NOT your band size we just calculated) from your cup measurement (second number).

3. Round up the difference to the next whole number and then look that number up on the chart below. This is your cup size. (Note: Lots of the higher end bra retailers use UK sizing so it’s worth noting both sizes depending on where you end up shopping.)

Here’s a quick example using my own measurements.

1. Measuring my torso below my breast tissue (and remembering to have the tape measure snug) I get 30″.

2. Then, with my back parallel to the floor, I measure around my breasts, holding the tape just barely snug enough so that it doesn’t fall off, but also doesn’t pull my breasts in. This measurement is 37″.

3. Using our above formula that makes my band a 30 and my cup a US G or UK F.

All bra websites I looked at have their own bra calculator or bra fitting instructions to help you find your best size. It’s worthwhile to look these over and compare to your own measured size before ordering. I’d still stick with the size you measured yourself, but if you notice a big difference it may still be worth ordering a couple sizes to see which fit you like better.

Here’s a great online calculator that you can use to compare your findings. (I recommend putting your most snug band size into this calculator as they tend to go large on band size)

Here’s another great calculator you can use to compare your findings.

A quick note about UK cup sizing: I’ve included UK cup sizes on the chart above because many of the higher end, quality bra makers use this sizing. As you can see US and UK sizing is the same through a D cup. Above that US bra makers can be all over the board, some even wanting to avoid labeling anything larger than a D cup so they’ve renamed the G cup DDDD. It’s a bit ridiculous, but something to be aware of when you are shopping.

Tips on Bras for Pregnancy & Nursing

One of the tricky aspects of being pregnant is the constant changes your body goes through.

Not only do your breasts typically change shape and size, but your rib cage can also expand. Sometimes this is a gradual change and sometimes it changes off and on the entire pregnancy. So fun! 😉

But now the question is, what do you do about your bras?

Maternity Bras

They do make bras specifically for maternity wear. They are usually free of underwire and have wider straps for comfort. They are also made of natural breathable fabrics like cotton and have extra sets of hook and eye closures on the back.

I think it’ll depend on your personal preference, but if you find your boobs change early on in your pregnancy this is probably a great route to go. It’s easy to say “oh, I can suffer for a short while”, but, let’s face it, you are pregnant for the better part of a year and as if that’s not uncomfortable enough, you don’t need to be crying in pain from your bra being too tight.

You can also buy bra extenders which is just an additional section of hook and eyes you can add to the back of your bra band. If you don’t need more room in the cups, this is a really great and inexpensive option! You can typically get these for $10 or less even in multi-packs like this one or this one.

Nursing Bras

Nursing bras come in a wide variety of sizes, styles and materials with the main distinguishing perk that the cup can un-clip and fold down to nurse and then clip it back. I don’t know who could nurse without having some good nursing bras, but figuring out the best size can be tricky.

Our bodies can change and fluctuate so much during this season, so there’s an inevitable amount of guesswork, especially if you want to have some on hand for right after you deliver your baby.

My suggestion is to use a store with easy returns (like Amazon!) and order a bunch of nursing bras a few weeks before you’re due in a couple sizes.

What size do you order? The size you are at that moment and maybe a size up for when your milk comes in. This way you have some options on hand a week post-partum and can return those that don’t work.

Let’s Buy A New Bra!

Confession: Up until now (and except for nursing bras) I’ve been a Victoria’s Secret girl. I’ve been fitted there multiple times and always grab some new bras when they have their semi-annual sale. But now that I’ve learned everything above (woot woot!) I feel like I’ve been a bit misled (whomp whomp).

They actually don’t even make my size, which is probably why I’ve been wearing the wrong size for most of my life. Admittedly, if they did carry my new, CORRECT size I’d still buy from them occasionally (I’m a girly girl, I love pink and frills and they are so pretty!), but I suggest sizing yourself, find some good quality every day bras and then buying fun ones there if you want (and if they carry your size).

That being said, while I am far from knowing all the bras there are in the bra world, I did compile a list of great online retailers to buy bras at.

If you’re like me, I rarely have kid-free time to go shopping and I love the ease of buying online and often being able to return for free.

Pretty much all bra websites have fit guides for their specific brand. It’s always helpful to check against their chart because different brands will fit you differently.

(Affiliate links)

• Third Love (www.thirdlove.com): Third Love has a fit guide that walks you through step by step to find your size. You can try the bra for free for 30 days (just pay 2.99 shipping) and you only get charged if you choose to keep it or if you don’t return within 30 days. Bras start at $68 and you get discounts for ordering multiples ($15 off 2 bras, etc).

• Wacoal (www.wacoal-america.com): Wacoal has some great resources, including a Bra Finder and a Bra Fit Calculator. They offer free shipping over $70 and free returns on any unworn bras within 60 days of purchase. Sizes range from 30A – 46H and I saw prices as low as $30 and ranging up to $70 (Tip: click “all bras” under the Bra header and then you can filter by size). Wacoal bras are offered in many department stores as well and you can use their store locator to find a location near you. I found these to be highly recommended by numerous sources.

• Anita (www.anita.com): One of my favorite nursing bras is this brand. Anita offers free shipping both ways and has a fantastic selection of specialty bras like nursing (19 options!), maternity and mastectomy bras. These bras are also sold in local retailers and you can use their store locator to find one near you. Sizes range from 30AA – 48J and prices start around $60 and go up to over $100.

• Panache (buy here on Amazon): Panache is a UK based company for D+ cups. Amazon has a good selection of styles and most have free shipping both ways!

• The Little Bra Company (www.thelittlebracompany.com): This brand is made specifically for small and petite women. Sizes range from A – C cups in band sizes from 28 – 38. Orders over $100 get free shipping. They have a great “Fitting Room” section on their website to help you find your size as well.

• LuLa Lu (www.lulalu.com): All LuLa Lu bras are for small breasted women in cup sizes AAA, AA, & A. They have free shipping within the US and appear to be a great resource for the smallest cup sizes.

• Amazon (www.amazon.com): As always, Amazon is a great resource. You can buy multiple styles, sizes, and brands and most have free shipping and free returns even without a Prime account. Always a win!

• Bra Stop (us.brastop.com): Bra Stop is out of the UK and has fabulous prices on good quality bras in cup sizes D – K. The merchandise does ship out of the UK, although their website says 5-10 business days for standard delivery (free over $90) which isn’t bad at all. Returns and exchanges are definitely trickier though. You have to pay shipping back to them, although if you’re making an exchange, they’ll send you the replacement free of charge. I can definitely see utilizing this resource once I was confident about my bra size and what fits.

• Pepper (wearpepper.com): This brand is made for cups AA-B, with band sizes from 30-40. Orders over $99 get free shipping and they do free returns and exchanges too! 

If you want to shop in-store, I suggest going to a higher end department store like Nordstrom’s or Macy’s, or, even better, an independent bra or lingerie shop in your local area. Often these have well trained staff that know exactly what they are doing.

They can help with fit and style and often have a wide variety of brands to choose from.

Proper Care of Your Bra

Last (but not least), if I’m going to encourage you to find that perfect size and then spend your hard earned money to buy quality bras, I want to give you a few tips on making your bras last!

1. Always hand wash or wash in a lingerie bag. A great tip I found said to wear your bra in the shower and gently hand hand wash while you are in there. Kills two birds with one stone! Even better would be to soak them in mild detergent for 10 minutes before gently spot cleaning and washing them, making sure not to wring the water out when you’re done, but instead gently squeezing it out.

2. Never, EVER put your bras in the dryer. Using the dryer can not only damage any lace or ribbon, but also ruins the fibers and elastic much quicker. Always air dry! If you shower at night you could easily hand wash it while you’re in there, hang over the shower rod to dry and it’d be ready the next morning! I typically hang mine by one strap, but it would be even better to hang it on a hanger so both straps carry the weight of the drying bra.

3. Never store your bras with one cup inverted into the other. This will destroy the padding and elasticity of your cups. The best way to store your bras is to lay them flat, nesting one bra into the other.

4. Ideally, you shouldn’t wear the same bra day after day, but instead swap between two every day bras so that you do not wear them out as quickly. Wash after 3-4 wears unless you’ve been working out or had lots of physical activity that produces sweat.

Join the Conversation

Prompt: Did you learn something new? Are you going to use the steps above to find your perfect new size? We’d love to hear your thoughts!

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