Bras have come a long way from handkerchiefs. It’s not that hyperbolic to say that bras as we know them are works of art and engineering. After all, they are designed to support weight , likened to a cantilever bridge.

There are many components to a bra, but little standardization regarding the language used to speak about these parts. Let’s break them down now: it’s time for bra anatomy!

Bridge, center gore, or center front – The space between the two cups.

The important part of this feature is that it respects the distance between your breasts, as well as the shape of your breast root, so the fabric applies the right tension to the underwire so that it is sprung.

The center gore is the point of stable equilibrium such that the rest of the bra stays put. If you’re noticing that the gore is not stable, chances are, the rest of your bra isn’t either!

It should be “sinking” or “tacking,” which means that it is lying flat against your sternum. It doesn’t always sink: for example, you could have a protruding or inwards facing sternum, or you could also very little space between your breasts.

Frame – The stable part of the bra, designed to exert tension around the rib cage.

This is the foundation to the cups, so that they’re not moving around all the time! If the bridge and the frame are incorrect, it’s difficult to evaluate the fit of the cups.

Wing or back band – Part of the frame that provides support and comfort for the rib cage as you inhale, exhale, and expand.

Made of powernet fabric that is stretchy so that you can breathe but firm enough to keep everything in place.

Underwire – Wire inserted beneath the breast root in supportive bras.

It is difficult to guarantee the stability of the bra frame unless the underwire is present and sprung under tension. Without the metal, fabric will collapse under breasts…which can weigh 5-10 pounds, and maybe even more!

Underwire engineering woes can include:

Cross-sections of an underwire. Patent US7207861.

Over-springing – If the underwire gauge is too light and the band too snug, the underwire will begin to torque into an “S” shape… which means that the underwire can poke into the sternum and side.

– If the underwire gauge is too light and the band too snug, the underwire will begin to torque into an “S” shape… which means that the underwire can poke into the sternum and side. Under-springing – If the Wing of the bra is not exerting enough force, the underwire could be sitting very loose in its casing. This allows for it to wiggle when you don’t want it to! You can observe this happening in bras that are not snug enough in the underband.

– If the Wing of the bra is not exerting enough force, the underwire could be sitting very loose in its casing. This allows for it to wiggle when you don’t want it to! You can observe this happening in bras that are not snug enough in the underband. Inappropriate strength – If the underwire is too heavy of a gauge, meaning that the cross section of the underwire is too thick, it can be highly uncomfortable on a body with smaller breasts. If the underwire is too light for the load it is meant to support, it will collapse under the weight of the breasts. Remember… a larger mass needs a stronger underwire, and a smaller mass does not need a nuclear grade underwire!

Straps – Designed to keep the bra up. While the band supports the majority of the mass, the straps help out.

The wider, the more comfortable! The thinner, the more they will dig.

Band elastic – A way to finish raw edges, and apply special tension to the underband. Typically, you want a little extra tension from this elastic application to help with the underwire sitting in place.

Again, the wider, the more comfortable. Tension of the elastic will also affect fit!

Hooks and eyes – Clasp used on back of bra to achieve the desired support.

This is a genius invention (especially if we think of the alternatives, like velcro and buttons). Unfortunately, the hooks and eyes do not work for everyone, depending on your mobility. Other bras will feature front closures or over-the-head options.

There’s an age-long debate on where a well-fitting bra needs to land on the hooks and eyes. Some say you want to optimize for a bra that fits on the loosest hook so that you have room to adjust it as the elastics stretch; others say the middle hook so you have room to eat, breathe, and bloat.

Other Components

Although these are the basics, there may be other features in your favorite bra. When we make a custom bra for a client, we add these special features for their particular needs:

Side sling or side cup lining – Provides extra support and moves breast tissue forward.

Side bone – Helps the frame maintain its stability.

Cookie – Used to account for asymmetry in the breasts.

Strap placement – Sometimes simply changing where the straps fall on the back makes a huge difference!

Which part of bra anatomy has you most intrigued? Let us know in the comments!