Fitting Guide

Purchasing lingerie online can be a daunting task - especially when your body is changing - so we've produced a thorough fitting guide to help ensure you get the perfect fit. If you still have questions or need additional assistance, please contact us, we're happy to help!.

Learning about maternity and nursing bras

Fitting Guide

Please note: Ma Mère stocks international designer brands and as a result, slight differences in sizing may be noticeable between brands.

The difference between maternity and nursing bras

The most obvious difference between a maternity and nursing bra is the special openings on a nursing bra that allow for convenient breastfeeding access. However, you'll probably need to purchase several different bra sizes over the coming months.

While it may seem logical to choose a nursing bra early in your pregnancy that could be worn throughout your pregnancy and while you breastfeed, this may not be the best solution.

The body changes significantly during pregnancy as the uterus and ribcage expand in preparation for the birth of your baby. Most women find their rib cage measurement will grow by 5 to 10 cm during pregnancy.

Once your baby is born, your hormone levels change and the ribcage begins to shrink and return to its pre-pregnancy size. Milk production begins, and the breasts take on a whole new size.

This means that the nursing bra purchased during pregnancy won't fit in the ribcage or cup size once the nursing or breastfeeding features of the bra are ready to be put to use. In addition, most bras will be so stretched that they would no longer provide adequate support.

Most maternity and nursing bras have a life of about 3-4 months because of ongoing changes that occur during pregnancy and nursing, as well as the stretching and relaxing of the fibres of the bra.

If you find the perfect fit in a nursing bra during pregnancy, bear in mind that it may not provide the best support when your baby arrives.

Maternity bra features:

  • More breast coverage to provide better support
  • More back hooks to allow for adjustment with changing rib cage size

Nursing bra features:

  • More breast coverage to provide better support
  • More back hooks to allow for adjustment with changing rib cage size
  • Special openings that allow for convenient nursing access
  • Various styles such as centre opening, pull-to-the-size, and top hooking to assist in breastfeeding


The importance of a good maternity and nursing bra

During pregnancy, special attention should be given to a well-fitted bra - one that not only supports your changing breast size, but promotes healthy functioning of the lymphatic and milk producing systems in the breast. Whilst some women change in size drastically and require several different sizes throughout their pregnancies, others change very little until the baby arrives and mature milk is produced.

A well-fitted maternity and nursing bra is important as it can offer significant cosmetic and health benefits.

Health benefits: Throughout the breast is a network of lymph glands and milk ducts. Unless these glands and ducts drain properly, discomfort and even infection can occur. When the breast is correctly supported, circulation improves, the lymphatic system functions properly, and the ducts drain.

Underwires are often avoided during pregnancy and nursing because they can provide an improper fit. Many women find their milk ducts extend back under their arms, so fitting an underwire properly can be challenging and may lead to blocked milk ducts.

Cosmetic benefits: Sagging is caused by the pull of gravity over time and is influenced by hereditary factors, breast size, and lack of muscle tone. Breasts, unlike any other parts of the body, have no muscles. The changes in breasts during pregnancy and nursing, and the lack of natural muscle support, mean that the chance of sagging or changes to breast shape is increased. A well fitted bra can provide the necessary support to maintain breast shape.


When to purchase maternity and nursing bras

The ideal time to purchase a bra for pregnancy is in the first trimester. Underwire bras worn before pregnancy can affect the development of milk ducts in some women and may cause breastfeeding complications.

Because of the changing hormone levels throughout pregnancy, the rib cage will continue to expand creating the need for larger band sizes, and the breasts will usually become fuller. As the belly and baby grow larger, so will the bra size.

Be prepared to purchase several different bra sizes during and after pregnancy. Most women typically buy fewer maternity and nursing bras than they would regular bras, which means they stretch out and show wear much sooner than regular bras. Frequent hand washing and line drying (in spite of care tag instructions to machine wash) will help maintain appearance and support.


A guide by trimester

First Trimester

For a proper fit, the bra should be hooked on the tightest back hook, and fit firmly but comfortably around the rib cage. Fitting the bra on the tightest hook allows for further ribcage growth during pregnancy.

The cup should provide enough depth to eliminate as much cleavage as possible. A cup that fits too snugly will not allow for growth throughout the pregnancy; however, a cup that fits too loosely will not provide adequate support and look crumply under the clothing.

Third Trimester

Prepare for breastfeeding your baby with the purchase of a T-shirt bra or camisole. These bras are more generic in size (i.e. size S, M, L, XL) and are generally very soft and stretchy to work best with the changing breast size during the first week. They offer light support during the time when you are probably recuperating with your baby. You can continue to wear your T-shirt bra or camisole at night to hold bra pads in place for leakage control and to provide light support for the months ahead.

Fourth Trimester

Once your baby has arrived and your milk is in, and any engorgement is resolved, it is time to get serious about a soft cup nursing bra that offers firmer support than your T-shirt bra or camisole has offered.

Your ribcage will have begun to shrink in size and your cup size should be consistent for several months. An ideal time to measure is within an hour before feeding time. This will allow for a cup that is generous enough to accommodate the fuller breast. Ladder hook cup adjustments in some nursing bras also allow for changes in cup size between feeding times.

A proper fit should eliminate as much cleavage as possible with no breast tissue spilling out the sides or over the top of the cups. The bra should be fitted comfortably on the loosest hook to allow for adjustment as the ribcage shrinks. Remember, your body is still going through significant change so the life of a nursing bra is usually 3-4 months, due to the frequent wearing and washing of the garment as well as the continual body changes.


Calculating your bra size

When measuring for a bra, it is important to understand that the fullness and individual shape of your breasts can influence the size that is best for you. Also, different brands, styles and fabrics can contribute to size differences. If you believe you are currently wearing the correct size we suggest you purchase it.

If you are unsure of your size, simply follow the steps below. The two most important measurements when calculating your bra size are band and cup measurements.

Step 1 - Band size

To calculate your band size, pull the tape measure around your ribcage underneath your breasts. Place the tape measure just underneath your bust at the front, making sure the tape measure is flat and straight across your back. Pull the tape snug and measure in centimetres.

Step 2 - Cup size

To calculate your cup size, repeat the measurement but this time measure across the fullest part of your breasts. Make sure the tape measure is fairly loose.

Underbust measurement in centimetres
  65 70 75 80 85 90 95 100
Band Size
Australia / New Zealand 8 10 12 14 16 18 20 22
UK / USA 30 32 34 36 38 40 42 44
Europe 65 70 75 80 85 90 95 100
France 80 85 90 95 100 105 110 115
Overbust measurement in centimetres
Cup Size A 77-79 82-84 87-89 92-94 97-99 102-104 107-109 112-114
Cup Size B 79-81 84-86 89-91 94-96 99-101 104-106 109-111 114-116
Cup Size C 81-83 86-88 91-93 96-98 101-103 106-108 111-113 116-118
Cup Size D 83-85 88-90 93-95 98-100 103-105 108-110 113-115 118-120
Cup Size DD 85-87 90-92 95-97 100-102 105-107 110-112 115-117 120-122
Cup Size E 87-89 92-94 97-99 102-104 107-109 112-114 117-119 122-124
Cup Size F 89-91 94-96 99-101 104-106 109-111 114-116 119-121 124-126
Cup Size FF   96-98 101-103 106-108 111-113 116-118 121-123 126-128
Cup Size G   98-100 103-105 108-110 113-115 118-120 123-125 128-130

Your ribcage will fall back to its natural place in the weeks and months afteryour baby is born, so you should initially fit a nursing bra on the loosest hook and then tighten it as your ribcage "shrinks". You should also be able to fit your hand inside the cup so that you have enough space for your breast pads.


Putting on your bra for a perfect fit

Maternity and nursing bras should support the entire breast, fitting comfortably withoutriding up. To achieve this, put your arms through the straps, hold each side of the bra, lean over to allow the breasts to "fall" into the cups, stand up straight, then hook the bra in the back. Reposition the breast tissue in the cup so the band is actually on the ribcage and not serving as the support of the breast tissue. Support is the job of the bra cup. Readjust the back hooks, if necessary, to a comfortable fit and adjust the straps.

If the back of the bra begins "riding up" it's a good indication that the bra is too large, and the bra band may need to be adjusted to a smaller size.


Checking the fit

The bottom of the bra, front and back, should be straight or slightly lower in back. Straps should not cut into the shoulders. The centre seam should lie against the breastbone without gaps between the cups. No flesh should overflow at the bra top, and the underseam area should lie smoothly without cutting the flesh. The cups should fit smoothly. Wrinkles in the cups may mean the bra is not properly fitted or breast tissue is not adjusted well in the cups.


Helpful tips - answers to common fitting problems

Baggy cups?
Try going down a cup size. However, if the cups are creasing around the nipple, try going down a band size to pull the fabric taught.

Spilling out of the tops or sides of your cups simply means that you're wearing too small a cup size. Try going up a cup size.

Tight shoulder straps?
A bra's main support comes from the band below the bust, not the straps. If the straps are digging in then they're taking too much weight, so go down a band size.

Riding high?
Look in the mirror side-on. Your bra band should be the same level all the way round. Riding up in back usually indicates the bra band is too large, providing insufficient support for the breast. Ironically, this riding up can actually cause the bra to feel too tight under the breasts. If it's riding up at the back, you should try going down a band size.

Too tight?
Your bra band should feel tight and firm and allow enough space for two fingers to fit under the back band. A maternity bra should initially fit on the loosest hook, whereas a nursing bra should initially fit on the tightest hook.

Unflattering shape?
The best way to see what shape a new bra will give you is to try it on under a tight fitting T-shirt. Look at yourself from all angles and make sure you get a smooth line with no unwanted lumps or bumps.