Underwire Bras — Are They Safe to Wear During Pregnancy?

Tracey Montford

By Tracey Montford

Jan 23, 2019

Can I wear an underwire bra during my pregnancy and/ or whilst pregnant? This is a key question that’s asked and we like to provide you with a comprehensive guide on the same.

There is insufficient evidence that correlates the wearing of a correctly fitted underwire bras to mastitis or other ailments. We believe that wearing an incorrectly fitting bra (wired or non-wired) will probably do your breast more damage. We recommend not wearing bras that are compressive, restrictive or overly tight in any manner.

We don’t recommend the use of underwire bras during the 1st three months of your pregnancy or the first 4-6 weeks post birth, when your breasts are fluctuating most. This is because the regular change in your breast (even by the hour) will inhibit it from fitting perfectly into the cup. The wires could therefore be a hindrance. When your bust has settled (outside of these period) a good fitting underwire bra will provide you with much desired shape, support and security.

At Cake, we design bras with a lighter, more flexible wire that has a wider smile too! Our flexible wire bras are designed to sit under and around your breast tissue, providing for a more desirable and flattering shape.

A flexible wired bra can be worn during appropriate times if fitted correctly.

What is the difference between a flexi-wire and an underwire?

What is an underwire bra?

An underwire bra is a bra that simply contains a wire in it. The wire is located in the wire channel (under the cups) and is supposed to sit under and around the bust, when on.

The wire is traditionally firm and pretty rigid. This is because the wire is needed to stretch the cup fabric over the bust, to provide the ideal amount of stretch and support. The wire is also required to sit reasonably firmly against the chest (centre and sides).

What is a flexi-wire bra?

A flexi-wire bra contains a lighter, more flexible wire in it. The flexible wire sits in the wire channel in much the same way as in your regular underwire bra, but is more supple and bendy.

Flexible wire can be made from metal, plastic and we’ve even seen some bras with rope inside the wire channel, to try and mimic the function of underwire.

So why do this, should be the question. The answer is to do with support, fit and safety!

There will be some change in the bust during your pregnancy and post, which is why flexi-wires are created to be forgiving. They try to re-create the fit & support, without being too rigid or firm.

Flexible wire designed for a maternity or nursing bra generally have a wider smile (curve) to help ensure that it sits comfortably below the breast tissue and not on it. This is particularly important as a pregnant or lactating woman will have fullness toward the top and side of her bust.

A flexible wire is generally softer and more malleable. Done correctly is not restrictive or uncomfortable to wear, but still gives the wearer good shape and added support.

What is the difference between a flexible wired bra and a normal gage wire?

A flexible wire is a thin soft gaged wire that is easily manipulated and bent. It is designed to move with your body rather than to sit firm and ridged. This makes it much more comfortable to wear and less intrusive.

Because a flexible wire is not has hard they can pull away in the centre front area of the bra. This is usually the case in the larger sizes. Smaller busted women will not notice such a problem.

A normal gage wire that is found in mainstream bras is usually much harder and less flexible. They are designed to sit firmly and can sometimes feel uncomfortable and restrictive, as they do not allow for ease of movement. Many women will take their normal gaged bras off at the end of the day as they find them uncomfortable to wear for long periods of time.

A rigid wire will sit neatly up against the breastbone pushing the bra in at the centre front. Separation of the breasts is much more apparent and greater levels of support are achieved.

Is an underwire bra safe to wear during my pregnancy?

A lot of women have been told not to wear underwire wire bras whilst pregnant and or breastfeeding due to a risk of mastitis or blocked milk ducts.

The truth is that there is simply no evidence that proves that wires are the cause of this problem, if the bra is fitted & worn correctly.

A flexible wire bra provides for the added safety net and can be viewed perhaps as a halfway situation been a non-wired bra and an underwire bra.

What can cause mastitis?

Mastitis can be caused by a number of different factors. Two main factors are:

1. The compression and or restriction of your breasts.

Restriction can be caused from wearing a bra that is too small or inflexible, as it will not allow for fluctuation or movement of the breast.

Solution:  Invest and wear a seamless bra during periods when your breasts are fluctuating dramatically in size. Rapid fluctuation is common for the first 4-6 weeks post partum as the body learns to regulate its milk supply (some women could experience an increase of up to 2 cup sizes between feeds as the milk supply regenerates).

Seamless bras come in easy sizing S-XL, and are made from a soft stretchy fabric that will move and stretch with your changing body. The beauty of these products is that they are not cupped size specific and will fit up to 5 cups sizes in each size. Making them the perfect choice for a rapidly changing bust.

2. Failing to empty the milk ducts completely after feeding.

It is generally advised to empty the breasts completely when breastfeeding your baby. Begin feeding on one side until the breast is empty then change to the other side. Alternate the side you start feeding on with each feed. Should your breast be left with milk in it, use a breast pump to help empty the excess milk.

Your body will learn to regulate its milk supply eventually and will only produce what your baby needs.

When can I wear a flexible wire?

It is advisable that you only wear a flexi-wire nursing bra once your breast growth has stabilised. This means we do not recommend wearing a flexi-wire bra during the first 8 weeks of pregnancy or the first 4 weeks post birth, as during these times a woman will experience changes in her breast size.

After your breasts have stabilised it is our recommendation that you get correctly fitted for your flexi-wire nursing bra by a professional bra fitter. Your bra size is likely to be very different compared with before. Wearing a correctly fitted bra will not only feel more comfortable on but will help to ensure you support your breasts correctly. A poor fitting bra can cause premature sagging and or ligament damage.

What the Australian Breastfeeding foundation has to say about flexible wired bras:

The ABA prescribes “There are now nursing bras available that have a flexible low-gauge wire support, designed to flex and change position with your changing shape. These are less likely to cause problems.”

Flexi-Wire Nursing Bras




Features and benefits of a good flexible wired bra

Cake Maternity specialise in designing beautiful underwire or flexi-wire nursing bras suitable for both pregnancy and breastfeeding. Our product choice is wide and ranges from Contour T shirt bras, feminine basics to beautiful fashion pieces.

1. The wire should be a thin gauge and easily manipulated

Most mainstream bras contain very hard-ridged wires that allow for no movement or flexibility, this is why wires can often be uncomfortable. A flexible wire however, will easily move and mould to you body giving the wearer a much more comfortable fit and ease of movement.

2. A good nursing or maternity bra will contain a flexible wire that has been constructed to sit under and around the breast

It has a much wider appearance compared with a mainstream bra wire. The benefit is that the wire will not sit up against the breast tissue if fitted correctly. It will set neatly under and around avoiding the breast tissue.

3. A good flexible wired bra will feel supportive and comfortable

The wire will help to create great shape and lift for a heavy bust. They are particularly beneficial for women with a large bust, as they will provide superior support.

4. Because of the flexible wire the design of the bra can be more flattering and versatile from under clothing

The centre front height can be lower which creates a more plunging neckline ideal for wearing underneath cute summer tops and sundresses.

How should my bra fit?

The wire should fit safely around the breast tissue and should not dig into the breast at any point. The flexible wire on a Cake Maternity bra has been especially designed to sit wider than that of a normal bra. This is because a women’s breast becomes very full during pregnancy and nursing, and we want to make sure it does not compress the breast.

A flexible wired bra should feel comfortable on and not restrictive in anyway.

They are ideal for women who are looking for extra support in a nursing bra. A lactating breast not only becomes bigger in size but it becomes much heavier too.

It will give you superior support, great shape and a fabulous profile.

Getting a great fit with a flexi-wire bra:

  • Visit your favorite lingerie boutique to get professionally fitted.
  • The flexible wire should sit neatly under and around the breast tissue. It should not dig in or feel uncomfortable.
  • Your breast should be sitting comfortably inside the cup of the bra. No tissue should be spilling out the top or sides of the bra. Nor should the cups have puckering or wrinkles.
  • The back band should sit firmly parcel across your back. It should be comfortable and not rid up or dig into your back tissue.
  • The flexible wire should help draw the center front of the bra into the chest bone. However, because the wire is much softer than a rigid wire found in mainstream bras, the center front will not sit flush against the chest bone.

Don’t miss: What You Need to Know About Seamless Nursing Bras

Like this post? Follow Cake Maternity on Facebook to get the latest updates!

You might also like...