What size nursing bra should I buy during pregnancy?

During pregnancy, your breasts typically increase 1-2 cup sizes. In your second trimester, buy nursing bras one cup size larger than your current size to accommodate growth. Choose bras with stretchy cups and multiple hook settings to adjust as your body changes.

When should I start wearing a nursing bra?

Most women start wearing nursing bras in the second trimester when regular bras become uncomfortable. You can wear them throughout pregnancy since they provide comfort without underwire and have room to grow. Have nursing bras ready before delivery.

How many cup sizes do you go up when breastfeeding?

When your milk comes in (around day 3-5 postpartum), breasts can temporarily increase 1-2 cup sizes due to engorgement. After 6-12 weeks, your size typically stabilizes but will still fluctuate between feedings. Most women are 1-2 cup sizes larger than pre-pregnancy while nursing.

Should nursing bras have underwire?

Avoid underwire during pregnancy and early breastfeeding as it can press on milk ducts and potentially cause clogged ducts or mastitis. Once breastfeeding is well-established (after 6-8 weeks), properly fitted underwire nursing bras are generally safe if they do not press on breast tissue.

How do I measure for a nursing bra?

Measure your underbust snugly for band size. For bust, measure at the fullest point when breasts feel moderately full (not engorged or just emptied). During pregnancy, add 1-2 cup sizes to allow for growth. Use our calculator for personalized recommendations based on your stage.

Nursing Bra Size Calculator

What this calculator does

Breast size changes substantially through pregnancy and breastfeeding, so a nursing bra bought at the wrong stage will not fit for long. Enter your measurements and your current stage — early, mid or late pregnancy, early or established nursing, or pumping — and this calculator gives your size now plus how it is likely to change from here.

Understanding Breast Changes During Pregnancy & Nursing

First Trimester

Breasts may increase 1-2 cup sizes. Tenderness is common. Consider wireless bras for comfort.

Second Trimester

Growth may stabilize. Good time to invest in nursing bras. Band size may increase as ribcage expands.

Third Trimester

Breasts preparing for milk production. May increase another cup size. Look for bras with room to grow.

Early Postpartum

Milk comes in around day 3-5. Expect significant engorgement. Size may increase 1-2 cups temporarily.

Established Nursing

Supply regulates around 6-12 weeks. Size stabilizes but still fluctuates between feedings.

Nursing Bra Calculator

Nursing & Maternity Bra Calculator

Current Measurements

Expected Size Changes

Recommended Bra Types

Shopping Tips for Your Stage

📌 Important Notes