Long past puberty, hormonal fluctuations continue to drive changes in the breasts. 

It’s pretty common for breasts to be uneven by up to a cup size, and more than half of us have some variation in breast size.

Of course, if you’re a borderline B, you’re not suddenly going to wake up with a pair of DDs. Yet most women notice differences throughout their monthly cycle, and it’s completely normal. 

Some common reasons for changes in breast size are the following:

• pregnancy

• breastfeeding

• hormonal changes throughout each menstrual cycle

• weight loss or gain

• aging.

Normal changes that you see in your breast size do not put you at any increased risk of breast cancer. You should, however, follow the recommendations for breast cancer screening for women of your age and family history.

If you notice a change in the size of your breasts that is different from your usual hormonal changes, see your doctor. Most of these changes are not cancerous or harmful, but it’s important that a doctor checks you to make sure.