Pregnancy and breastfeeding initiate some of the most significant breast changes a woman will experience in her lifetime. Your pre-pregnancy bras almost certainly won't fit during this journey, and many women find their size is different even after they've finished nursing. Understanding how to navigate bra fitting during and after pregnancy ensures you have comfortable, supportive options throughout this transformative time.
The key to post-pregnancy bra fitting is patience. Your body continues changing for months after giving birth, and trying to rush back to "normal" bras often leads to discomfort and poor fit. This guide will help you understand what to expect and when to invest in new bras at each stage.
Understanding How Pregnancy Changes Your Breasts
Breast changes begin early in pregnancy, often before you even know you're expecting. Hormonal shifts cause breast tissue to expand and become more sensitive. Many women go up one to two cup sizes during pregnancy, sometimes more, with changes occurring most noticeably in the first trimester and again toward the end of pregnancy.
The band size often changes too. Your ribcage expands to accommodate your growing baby, and many women find they need a larger band size by the third trimester, regardless of whether they've gained weight.
After giving birth, your breasts change again. If you're breastfeeding, they'll fill with milk and may become significantly larger in the early days. Even if you're not nursing, hormonal shifts mean your breasts won't immediately return to their pre-pregnancy state.
Bra Fitting During Pregnancy
During pregnancy, prioritise comfort and accommodation for your changing body. Many women transition to maternity bras, which are designed to grow with you throughout pregnancy. Look for bras with multiple hook settings, adjustable straps, and stretchy, forgiving fabrics.
Underwired bras are generally safe during pregnancy, but many women find them uncomfortable as their ribcage expands and breasts become more sensitive. Wireless maternity bras or soft-cup styles often provide adequate support with greater comfort.
You may need to buy bras more than once during pregnancy as your size continues to change. Some women find that buying a few inexpensive styles in their current size works better than investing heavily in bras that may only fit for a few weeks.
Nursing Bra Considerations
If you plan to breastfeed, you'll need nursing bras with easy-access features for feeding. These typically have clips or panels that allow you to expose one breast for feeding without removing the entire bra.
Timing the purchase of nursing bras requires some thought. Buying too early in pregnancy means you're guessing at what size you'll be when your milk comes in. Many experts recommend buying nursing bras in the last month of pregnancy, when you have a better sense of your late-pregnancy size.
Use our bra size calculator to check your size, then add approximately one cup size to account for milk production. This provides a reasonable starting estimate, though individual variation is significant.
In the early weeks of breastfeeding, your breast size may fluctuate considerably throughout each day depending on when you last fed. Nursing bras with stretch cups accommodate this fluctuation better than structured styles.
The First Months After Birth
Whether or not you're breastfeeding, the first few months postpartum are a time of significant physical adjustment. Your hormone levels are stabilising, your ribcage is returning to its normal position, and your breast tissue is settling into its new state.
If you're breastfeeding, continue with nursing bras for as long as you're nursing. Many women find that their size stabilises somewhat after the first few weeks, once milk supply regulates. However, ongoing fluctuations are normal.
If you're not breastfeeding or have stopped, resist the urge to immediately buy a full wardrobe of new bras. Your size may continue to change for several months as hormones settle and breast tissue adjusts. Soft, stretchy bras or bralettes are comfortable options during this transition.
After Weaning: When Will Your Size Stabilise?
After weaning, it typically takes three to six months for breast tissue to settle into its post-nursing state. During this time, breasts often decrease in size as milk-producing tissue is replaced by fatty tissue. Some women find they return to their pre-pregnancy size; others settle at a different size permanently.
Changes in breast shape are also common. Many women notice their breasts are softer, less firm, or sit differently on their chest than before pregnancy. This may affect which bra styles work best for you going forward.
Wait until approximately three to six months after weaning before investing in new everyday bras. At this point, your size should be relatively stable and will serve as your new baseline.
Measuring Yourself Post-Pregnancy
When you're ready to determine your post-pregnancy bra size, follow the standard measuring procedure. Use our Australian bra size calculator for accurate results. Measure your underbust snugly around your ribcage, and measure your bust at the fullest point.
If you've recently finished breastfeeding, measure at a time when your breasts feel neither particularly full nor particularly empty. Morning measurements after you've been upright for a while tend to be most representative.
Don't be surprised if your post-pregnancy size differs from your pre-pregnancy size. Some women go up a cup size permanently; others go down. Band size may change too, depending on how your ribcage has settled. Whatever size the calculator provides is your new starting point—try not to compare it to what you wore before.
Choosing Styles for Your Changed Body
Post-pregnancy breasts may have different needs than they did before. Women who previously wore push-up bras might find they prefer full-coverage styles that provide more support and lift. Those who had firm, self-supporting breasts may now benefit from more structured bras.
If you've experienced significant changes in breast shape—particularly if your breasts have become softer or less projected—you might find that different cup shapes fit better than before. Balconette styles often work well for breasts that have settled lower on the chest, providing lift and creating a more centred appearance.
Take time to try different styles and brands. Your preferences and needs may have genuinely changed, and what fit perfectly before pregnancy might not be your ideal style going forward.
Embracing Your Postpartum Body
It's worth acknowledging that post-pregnancy bra fitting can be emotionally charged. Your body has done something remarkable, and it's normal for that to leave lasting changes. Try to approach bra fitting with curiosity rather than expectation—the goal is finding what fits and feels good now, not recreating your pre-pregnancy silhouette.
Many women find they actually prefer their post-pregnancy breasts and the bras that suit them. Different doesn't mean worse; it simply means you're at a new stage of life with new fitting requirements.
Start fresh with our bra size calculator, explore different styles with an open mind, and celebrate finding bras that support and flatter your body as it is today.