Breast measurement involves the

measurement Measurement is the quantification of attributes of an object or event, which can be used to compare with other objects or events. In other words, measurement is a process of determining how large or small a physical quantity is as compared to ...

of the

breast The breasts are two prominences located on the upper ventral region of the torso among humans and other primates. Both sexes develop breasts from the same embryology, embryological tissues. The relative size and development of the breasts is ...

s for quantifying physical characteristics such as

size Size in general is the Magnitude (mathematics), magnitude or dimensions of a thing. More specifically, ''geometrical size'' (or ''spatial size'') can refer to three geometrical measures: length, area, or volume. Length can be generalized ...

, shape, and

developmental state Developmental state, hard state, State-led developmentalism or in some cases Neo-developmental state, is a term used by international political economy scholars to refer to the phenomenon of state-led macroeconomic planning in East Asia in the la ...

. A variety of different approaches have been employed for measuring the breasts.

Tanner staging

Tanner staging The Tanner scale (also known as the Tanner stages or sexual maturity rating (SMR)) is a scale of physical development as pre-pubescent children transition into adolescence, and then adulthood. The scale defines physical measurements of developm ...

can be used to assess the developmental state of the breasts during

puberty Puberty is the process of physical changes through which a child's body matures into an adult body capable of sexual reproduction. It is initiated by hormonal signals from the brain to the gonads: the ovaries in a female, the testicles i ...

, from childhood (Tanner stage 1) to adulthood (Tanner stage 5).

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 cast A plaster cast is a copy made in plaster of another 3-dimensional form. The original from which the cast is taken may be a sculpture, building, a face, a pregnant belly, a fossil or other remains such as fresh or fossilised footprints – ...

ing,

medical imaging Medical imaging is the technique and process of imaging the interior of a body for clinical analysis and medical intervention, as well as visual representation of the function of some organs or tissues (physiology). Medical imaging seeks to revea ...

(e.g.,

mammography Mammography (also called mastography; DICOM modality: MG) is the process of using low-energy X-rays (usually around 30 kVp) to examine the human breast for diagnosis and screening. The goal of mammography is the early detection of breast cance ...

magnetic resonance imaging Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to generate pictures of the anatomy and the physiological processes inside the body. MRI scanners use strong magnetic fields, magnetic field gradients, and ...

(MRI),

ultrasound Ultrasound is sound with frequency, frequencies greater than 20 Hertz, kilohertz. This frequency is the approximate upper audible hearing range, limit of human hearing in healthy young adults. The physical principles of acoustic waves apply ...

), and

3D scanning 3D scanning is the process of analyzing a real-world object or environment to collect three dimensional data of its shape and possibly its appearance (e.g. color). The collected data can then be used to construct digital 3D models. A 3D scanner ...

. There is substantial

measurement error Observational error (or measurement error) is the difference between a measured value of a quantity and its unknown true value.Dodge, Y. (2003) ''The Oxford Dictionary of Statistical Terms'', OUP. Such errors are inherent in the measurement pr ...

with many breast volume measures, but MRI imaging appears to have among the lowest error and hence to be the most accurate measure. However, 3D scanning might have the potential to become the new gold standard for clinical assessment. A limitation of 3D scanning is inaccuracy in the case of large and/or ptotic. In a normative study of breast volumes in cisgender women using 3D scanning, breast volumes were median 515mL, mean 650mL,

interquartile range In descriptive statistics, the interquartile range (IQR) is a measure of statistical dispersion, which is the spread of the data. The IQR may also be called the midspread, middle 50%, fourth spread, or H‑spread. It is defined as the differen ...

310 to 850mL, and range ~50 to 3,100mL. In transgender women, breast volume measured with 3D scanning has been reported to reach a plateau of around 100mL (but with an apparent range of up to 750mL) after 3 to 4years of hormone therapy. Breast volume has also been assessed with the BreastIdea Volume Estimator (BIVE), a freely available web application that uses user-provided photographs and anthropometric measurements to calculate estimations of breast volume. It has been studied and validated in cisgender women and men, women with

macromastia Breast hypertrophy is a rare medical condition of the breast connective tissues in which the breasts become excessively large. The condition is often divided based on the severity into two types, macromastia and gigantomastia. Hypertrophy of the ...

gigantomastia Breast hypertrophy is a rare medical condition of the breast connective tissues in which the breasts become excessively large. The condition is often divided based on the severity into two types, macromastia and gigantomastia. Hypertrophy of the ...

, and transgender women. Average breast volumes have been reported to be 272 to 283mL (range 99–694mL in one study) in cisgender women, 888mL in women with macromastia or gigantomastia, and 158 to 190mL (range 20–788mL) in transgender women after 6months of hormone therapy. The resolution and accuracy of the BIVE is less than with 3D scanners.

Breast circumference

Breast circumference, also known as bust circumference, is a measurement of the

circumference In geometry, the circumference () is the perimeter of a circle or ellipse. The circumference is the arc length of the circle, as if it were opened up and straightened out to a line segment. More generally, the perimeter is the curve length arou ...

of the

torso The torso or trunk is an anatomical terminology, anatomical term for the central part, or the core (anatomy), core, of the body (biology), body of many animals (including human beings), from which the head, neck, limb (anatomy), limbs, tail an ...

at the level of the breasts. It has been used as a measure of breast size in normal young women, in women with

pregnancy Pregnancy is the time during which one or more offspring gestation, gestates inside a woman's uterus. A multiple birth, multiple pregnancy involves more than one offspring, such as with twins. Conception (biology), Conception usually occurs ...

,Drąsutis, J. (2017). Krūtų morfologinių parametrų, kūno dydžio bei formos ir kraujo serumo prolaktino bei lipidų kitimai per nėštumą, daugialypės šių rodiklių sąsajos ir sveikatos rizikos morfologiniai žymenys (Doctoral dissertation, Vilniaus universitetas). https://epublications.vu.lt/object/elaba:23065971/ and in

transgender women A trans woman or transgender woman is a woman who was assigned male at birth. Trans women have a female gender identity and may experience gender dysphoria (distress brought upon by the discrepancy between a person's gender identity and their ...

. Breast circumference is generally measured using a flexible fabric

tape measure A tape measure or measuring tape is a long, flexible ruler used to measure length or distance. It usually consists of a ribbon of cloth, plastic, fibreglass, or metal (usually - hard steel alloy) strip with linear measurement markings. Types Ta ...

, and is the circumference across the breasts over the

nipple The nipple is a raised region of tissue on the surface of the breast from which, in lactating females, breast milk, milk from the mammary gland leaves the body through the lactiferous ducts to Breastfeeding, nurse an infant. The milk can flow th ...

s to the

back The human back, also called the dorsum (: dorsa), is the large posterior area of the human body, rising from the top of the buttocks to the back of the neck. It is the surface of the body opposite from the chest and the abdomen. The vertebral c ...

. The breast–chest difference is breast circumference minus band or underbust circumference and is used in the determination of bra cup size.

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 underbust circumference. Breast–chest difference has been used in the measurement of breast development in

feminizing hormone therapy Feminizing hormone therapy, also known as transfeminine hormone therapy, is a form of Transgender_health_care#Gender-affirming_care , gender-affirming care and a gender-affirming hormone therapy , gender-affirming hormone therapy to change t ...

Bra size

Breast hemicircumference

Breast hemicircumference, also sometimes referred to as breast width or as breast circumference ( incorrectly), is an anthropometric measure of the breasts which has been used in studies to assess breast development and breast size, including in

. It is the medial horizontal length (measured with a flexible tape measure) from one side of the breast to the other side and running over the nipple. A measurement of 7inches is said to correspond to an A cup, 8inches to a B cup, 9inches to a C cup, and so on, with each further 1-inch increment or decrement corresponding to one cup size up or down.

Breast unit

The breast unit is a measurement of the breasts in which the breasts are measured horizontally and vertically and then these values are multiplied to given 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: The breast unit has also been used to quantify breast size in girls and women with

complete androgen insensitivity syndrome Complete androgen insensitivity syndrome (CAIS) is an AIS condition that results in the complete inability of the cell to respond to androgens. As such, the insensitivity to androgens is only clinically significant when it occurs in individual ...

(CAIS) and other individuals with disorders of sexual development. It can also be reported unmultiplied (e.g., 16×14 cm to 41×31 cm in CAIS women).

Other breast measurements

Other measurements of the breasts, like areolar diameter, can also be determined.

References

{{Reflist Anthropometry Breast