Why are breasts different sizes?

During puberty, breasts don't always receive identical amounts of the hormone that makes them grow. Why does this happen, and how common is perfect symmetry anyway?

The 14 Best Bras for Asymmetrical Breasts of 2024

The Right Bra for Breasts of Different Sizes?

Why do women's boob sizes vary? - Quora

Breast Asymmetry: 9 Reasons You Have Uneven Breasts - HealthyWomen

8 Common Breast Changes During Pregnancy

Infographic: How to find a bra that fits : Life Kit : NPR

Is It Normal to Have Different-Sized Breasts? - GoodRx

My breasts are different sizes – how do i find the right bra?

Why your breasts are not the same size