Breast Development and Breast Size

The same way that some women are short or tall, some women have large breasts, some have medium-sized breasts, and others have small ones. Some reach their full breast size early, and others much later. Some breast pairs even come in different sizes from each other. Some women have inverted nipples, and others have flat ones. Breast colors can vary, and so can nipple sizes. Just about any size, shape and color is normal, even when breasts are lopsided or different from each other.

When does breast development begin? It varies a great deal among girls. Some begin breast development as early as nine years of age, while others don't begin until about fourteen years of age. Both ages are normal, and so are any ages in between. Usually, a girl's breasts will begin to grow within a year of the time her mother's breast development began.

As girls reach puberty, the first outward signs of breast development are noticeable. When a girl starts menstruating, her breasts begin to mature by forming glands at the end of the milk ducts. The time and rate of this growth is different for every girl. Most young girls follow these five stages of breast development:

Once breast development begins, it's important to begin thinking about taking care of those breasts with some good support. A good bra can protect the breast tissue and keep the breasts supported, especially if a young girl is active in sports or other activities.

How do you determine breast size to get a well-fitting bra? Breast size can be broken down into two parts, the chest size and the cup size. A number represents the chest size, and a letter represents the cup size. For example, if your chest measurement is 34 and your cup measurement is B, then your breast size is 34B.

To find your breast size, use a tape measure and follow these steps. Start just under your breasts and run the tape measure all the way around your back. Keep it tight but don't squeeze the skin. Note the measurement and add 5 inches. That number is your chest size.

Next, use the tape measure across the most full part of your breasts and all the way around your body. Note the number, and then subtract the chest size from it. The difference between the two numbers indicates your cup size.

For example, if your chest measurement was 32 and your cup measurement was 34 that's a 2-inch difference, so your breast size would be 34B.

You may notice that your breast size is an odd number, but that bra sizes only come in even numbers. If your chest measurement is an odd number, such as 31 or 33, you should round up. This will allow room for growth, and you can use the adjustment straps for a tighter fit if needed.

If you have trouble measuring your breast size or are unsure if you are doing it correctly, don't worry. Most stores that sell bras have people trained to help you measure breast size and get a well-fitting bra. Simply ask an associate in the bra department to help you find the best fit.

Resources

Akron Children's Hospital. (2004, July). Menstruation and breast exam [KT-409].

Kid'sHealth for Kids. (2004). Breasts and bras. Nemours Foundation.

Litt, I.F. (2004). Breast development Q & A.

Lucile Packard Children's Hospital at Stanford. (2004). Normal breast development.