- Breast Volume
Breast volume is a method of measuring the size of the breasts. A variety of techniques have been used to measure breast volume, including water displacement, plaster casting, medical imaging (e.g., mammography, magnetic resonance imaging (MRI), ultrasound), and 3D scanning. There is significant measurement error with many breast volume measures.
Still, MRI imaging appears to have among the lowest error. Hence, it is the most precise measure.
Nonetheless, 3D scanning has the potential to become the new gold standard for clinical assessment.
In a normative study of breast volumes in women using 3D scanning, breast volumes had a median of 515 mL. The mean volume was 650 mL. The interquartile range was 310 to 850 mL. The overall range was approximately ~50 to 3,100 mL.
In transgender women, researchers have reported that breast volume measured with 3D scanning tends to plateau at around 100 mL. This occurs after 3 to 4 years of hormone therapy. However, it has an obvious range of up to 750 mL.
The average breast volume in normal women has been reported to be 272 to 283 mL. One study reported a range of 99–694 mL. In women with macromastia or gigantomastia, it is 888 mL. In transgender women after 6 months of hormone therapy, it is 158 to 190 mL (range 20–788 mL).
- Breast Circumference
Breast circumference, also called bust circumference, measures the torso’s girth at the level of the breasts. It is used to assess breast size in women, including young, pregnant, and transgender women. It is measured with a flexible tape across the breasts at the nipples.
The difference between breast circumference and underbust circumference determines bra cup size.
- Bra Size
Bra size is also known as bra cup size. It is a measurement of the breasts for selecting bras. This takes into account breast size and torso circumference. It is determined using the breast–chest difference. A measurement of 12–14 cm equates to an A cup. A measurement of 14–16 cm means a B cup. The difference of 16–18 cm indicates a C cup. Lastly, 18–20 cm equates to a D cup.
- Breast Chest Difference
Breast–chest difference, also known as bust–band difference, is a measurement used for quantifying breast size. It is calculated as bust circumference minus the band or under bust circumference. Breast–chest difference has been used in the measurement of breast development in transgender women on feminizing hormone therapy.
- Breast Hemi Circumference
Breast hemi circumference is also referred to as breast width. Sometimes, it is incorrectly called breast circumference. It is an anthropometric measure of the breasts. This measure has been used in studies to assess breast development and breast size, including in transgender women.
It is the medial horizontal length. This length is measured with a flexible tape measure. It spans from one side of the breast to the other side and runs over the nipple.
A measurement of 7 inches corresponds to an A cup. 8 inches corresponds to a B cup. 9 inches matches a C cup. Each further 1-cm increment or decrement corresponds to one cup size up or down.
- Breast Unit
The breast unit is a measurement of the breasts. They are measured horizontally and vertically. These values are multiplied to give an overall idea of breast size. It was devised by Vincent J. Capraro and has been used in pediatric endocrinology to quantify breast development. The method has been described as follows:
At times it is desirable to know if a girl’s breasts are developing normally. This can be done by observing their increasing size over several months. In some cases, it is also advantageous to determine if there are differences in the sizes of the two breasts. It’s important to consider if these differences are of clinical significance. To more accurately measure breast size, one of us (V.J.C.) devised a technique for breast measurement. This technique may be used in following up the development of normal breasts. It can also be used for breasts showing asymmetric development. With a centimeter tape measure, the breast is measured from 3 o’clock to 9 o’clock (Fig. 23-4, A) and from 12 o’clock to 6 o’clock (Fig. 23-4, B). These two measurements are multiplied, yielding a figure called the breast unit. Table 23-3 shows the typical spread of breast units in a normal adolescent.
The breast unit has been used to quantify breast size in girls with Complete Androgen Insensitivity Syndrome (CAIS). It is also applied to women with CAIS. It is also used for other individuals with disorders of sexual development.
Breast Types
Archetype
The archetypal breast is round and full. It has a small point at the nipple. This shape is considered the “standard” for breast type.
It’s said to be the most common shape, so it’s what most bra manufacturers model their designs after.
East west
Asymmetric
A pair of breasts where the shape of breasts is different is called an asymmetric pair. Either of them could be noticeably bigger or less pronounced. More than half of people have some variation between breast size.
Round
•A round shaped pair is the one in which the breasts are equally full at the top and the bottom.
Close set
•Close-set breasts have no separation or a very small gap between them. They sit closer to the center of your chest, creating more distance between your underarm and your breast.
Conical
Conical breasts have a cone-like shape, which is more common in smaller breasts.As breasts grow, they usually become rounder. However, some women’s breasts remain conical throughout their lives. This is usually due to genetics or hormonal factors. Conical breasts are perfectly normal and healthy. Some women may feel self-conscious about their breast shape, but there is no medical reason to change them. If you are concerned about the shape of your breasts, you should speak to your doctor.
Bell Shape
•Bell-shaped breasts are characterized by a slimmer upper portion and a fuller lower portion, resembling the shape of a bell.
Tear Drop
•This shape is like bell-shaped breasts but with a gentler slope. They are less full at the bottom than bell-shaped breasts.
Slender
•Slender breasts are wider at the top and narrower at the bottom. They are skinny and have less breast tissue.
Athletic
••Athletic breasts are tight, wider with more muscle and less breast tissue and upright nipples..
Relaxed
••Relaxed breasts are wider at the top and narrower at the bottom with nipples facing downward.
What determines breast shape?
Once you have determined your breast shape, you might question the reasons behind it. Several factors contribute to the shape of your breasts.
•Genetics play the most significant role in determining breast characteristics. They influence breast density, tissue composition, size, among other aspects.
•Weight. Fat is a large part of your breast tissue and density. You may notice a difference in your breast shape as you gain or lose weight.
- Weight Loss: When you lose weight, the cells in fat tissue shrink, including those in the breasts. Additionally, each time you gain or lose weight, the skin around your breast tissue loses elasticity, affecting its ability to contract to the new breast shape
- Weight Gain: Fat tissue makes up a large part of breast tissue. When you gain weight, fat cells in the breasts expand, which can alter breast shape. People with larger chests have more fat tissue. They do not necessarily have more duct or lobule volume (the lean tissue required for breastfeeding).
•Exercise: Your breasts might look firmer or perkier. You can achieve this by strengthening your pecs, which builds up the muscles behind your breast tissue. Some exercises to try include chest presses, push-ups, and dumbbell flyes. Remember to consult with a fitness professional before starting any new exercise program.
•Age: Your breasts will naturally sag as you get older. Over time, your breasts may become longer. They may also shift to face downward.
•Pregnancy & breastfeeding: Your hormones during pregnancy and breastfeeding can make your breasts swell. They change how the fat and tissue are distributed throughout your breasts.