If you’re pregnant or newly postpartum and wondering if you should size up when buying a nursing bra or pumping bra, I can help! — I’ve been there too, more than once! As a mom of three who breastfed for eight years combined, I know firsthand how confusing it can feel when your body changes weekly and nothing seems to fit the same for long.

The truth is, finding your perfect nursing bra fit doesn’t have to be complicated. With the right design and a little expert guidance on fit, your nursing and pumping bras can transition with you through every stage of motherhood.

How Your Breast Size Changes During Pregnancy and Postpartum

During pregnancy, your breasts start to grow as you prepare for milk production and your ribcage also will expand to make room for your growing belly.  Our research showed that 3 out of 4 women reported their cup size growing 1-2 cup sizes while pregnant and feeling tighter around the bra band. After your baby arrives and your breastmilk comes in, you may additionally grow an additional cup size until your breast tissue regulates around 8-12 weeks postpartum.

These changes are completely normal, and that’s why a comfortable maternity bra that transitions to a hands-free pumping bra is such an essential piece of your wardrobe. At Davin & Adley, all of our nursing and pumping combo bras are designed to stretch and recover so you can wear the same bra through pregnancy, postpartum, and your entire breastfeeding journey, both nursing and pumping.

Why You Don’t Need to Size Up

If the bra you are purchasing is designed specifically for maternity and nursing, moms don’t need to size up.  When buying a nursing or pumping bra, it’s most important to follow the brand sizing guide and pick the correct size. With a proper fitted nursing and pumping bra, it will be designed to grow with you — and you will only need a few bras built for this stage of life. Quality nursing and pumping bras will last you many years.

When I designed Davin & Adley nursing and pumping bras, I made sure each style had the flexibility to adjust through pregnancy, postpartum, and beyond — without you needing to buy multiple sizes along the way. Always look for nursing and pumping bras made with stretchy, supportive materials that adapt to your body as it grows and changes. If you size up too much, you will lose the support you need in the bra band, and your pumping flanges may not stay secure during a session. Instead, I recommend grabbing a flexible tape measure or printing out our downloadable tape measure on our nursing bra size chart to confirm! It’s super easy and worth the extra step to get the right fit.

When Sizing Up Does Make Sense (sometimes!)

There are times when going up a bra size may be the right choice:

• You’re in your first trimester and you have several months left to grow.
• You’re in between sizes and prefer a relaxed fit instead of a snug fit.
• You experience fullness or engorgement and need the extra room as your supply regulates.
• Your chest is very large in the cup and you need our busty sizing instead.

How to Find Your Perfect Fit Nursing Bra

Your perfect nursing bra fit should feel supportive, secure, and comfortable all day long. Here’s a quick fit checklist I always share with my moms:

• The band should feel snug and supportive but not extremely tight. You want to feel secure but not have the elastic digging or cutting into you and making red marks!
• The cups should cover your breast tissue fully without gapping or spilling over the edge. You want your breasts to be supported but not squished. Too tight of a bra can cause breast trauma when breastfeeding!
• The straps should stay in place without digging in or falling off the edges, adjustable straps are a must for nursing and pumping.
• Your pumping flanges and wearable breast pumps should stay secure without slipping or digging in.

And if you’re unsure, don’t stress — we offer FREE personalized size consultations, a detailed nursing bra size guide, plus free exchanges to make sure you find your perfect fit.

The Bottom Line from a Mom Who’s Been There

You are not alone in this! You don’t need to guess your size or buy a drawer full of bras “just in case.” The right nursing and pumping bra will stretch with your changing body and support you through every feeding session and pump along the way.

At Davin & Adley, every bra I design is made to fit your motherhood journey — from your first trimester to your final pump session. You deserve comfort that lasts, support that adapts, and style that makes you feel like you again.

If you are ready to get started, check out my personalized links below!

• Nursing Bra Fit Quiz
• Schedule a FREE Bra size consultation
• Best-Selling Nursing & Pumping Bras