Second or third? To answer this question, it is enough to take measurements and do some calculations. We figure out how to determine the size of the breast and why it can change.

How to take measurements correctly

To determine the size of the bust, you need to know two parameters – the girth of the bust and the girth under the bust. All measurements are best taken without a bra. To be more comfortable, you can wear a loose T-shirt made of thin fabric. It is important that it does not constrain the chest.

You can take measurements yourself, in front of a mirror. But the measurements will be more accurate if someone helps you. Stand up straight and relax. You need to take the usual comfortable posture. Do not draw in the stomach, do not stick out the chest and do not deliberately straighten the back.

To measure underbust, pull the tape measure fairly tight. It should fit snugly around the body, but not dig into the skin.

The circumference of the chest is measured in two positions: standing and tilted. Measure at the most prominent points, without squeezing the breast tissue. If the difference between the standing and tilted measurements is no more than five centimeters, use the measurement taken in the tilt for further calculations. If the difference is more than five centimeters, you need to find the arithmetic mean: add the results and divide in half.

take breast measurements

How to determine the size of the chest

To determine your bust size, subtract the underbust measurement from your bust measurement.

The difference between bust and under bustBreast sizeMarking on the bra
up to 11 cm0AA
12-13 cmoneA
14-15 cm2B
16-17 cm3C
18-19 cmfourD
20-21 cm5E
22-23 cm6F

To choose a bra size, you need to focus on two parameters – the girth under the bust and the size of the cup. Markings from different manufacturers may vary, so when buying, you should check the size table.

Why does breast size change?


Before menstruation, the mammary glands swell a little and increase. This is normal, but it is better to plan the purchase of new underwear in the middle of the cycle. Otherwise, the bra may be too big when the size of the breast returns to normal.

Taking hormonal contraceptives

Breast size may increase due to the use of hormonal contraceptives. Usually after a few months the body adapts and the breast returns to its previous size.

Pregnancy and lactation

Breasts enlarge during pregnancy and breastfeeding. During this period, the size of the mammary glands can change several times a day, so it is convenient to wear special elastic underwear for nursing mothers.

Weight change

The breast consists of glandular and adipose tissue. If a woman has gained weight or lost weight, then the size of her breasts will also change. In such a situation, it is better not to buy bras of the usual size, but to take measurements again.