The most common complaint about any support garment — a band, a wrap, a faja, a nursing bra — is not that it was too weak or too strong. It is that it sat in the wrong place. It rolled down. It dug in on one side. It gapped at the top.
Almost every one of those problems traces back to sizing, and almost every sizing problem traces back to measuring the wrong spot or measuring at the wrong moment. This guide covers both.
Why the same size fits differently across brands
There is no international standard for postpartum or maternity sizing. A size M from one brand can correspond to a 30cm span of hip measurements; another brand's M covers a 20cm span at a different starting point. This is why "I'm usually a medium" is not useful information when ordering support wear.
The only reliable approach is to ignore your usual clothing size entirely and go by the numbers on the specific chart in front of you.
What you need
A soft fabric measuring tape. Not a builder's tape measure — it will not follow the curve of your body and will read short. If you do not have one, a piece of string and a ruler works: wrap the string, mark it with a pen, then lay it flat against the ruler.
Measure over bare skin or thin, close-fitting underwear. Measuring over a jumper adds several centimetres and will push you into the wrong size.
The four measurements that matter
1. Underbust
Wrap the tape directly under your bust, where a bra band sits. Keep it level all the way around — check the back in a mirror, because it tends to ride up. Breathe out normally and read the number then. Do not hold your breath in or push it out.
Used for: nursing bras, longer wraps, upper-body support garments.
2. Natural waist
This is the narrowest point of your torso, usually about 2cm above the belly button. If you cannot find it easily — which is common postpartum — bend sideways at the waist. The crease that forms is your natural waist.
Used for: most belly bands and waist-level wraps.
3. Belly button level
Measure straight around at the level of your navel, tape level with the floor. This is the measurement most postpartum support charts actually use, and it is the one people most often skip — they measure their natural waist instead and end up ordering a size too small.
Used for: postpartum wraps, abdominal binders.
4. Hip / widest point
Stand with your feet together and measure around the widest part of your hips and bottom. Feet together matters; a wide stance changes this reading by several centimetres.
Used for: fajas, high-waisted shapewear, longer-line garments.
When to measure
Time of day changes your numbers. Most people measure smallest in the morning and largest in the evening, and postpartum swelling can shift things considerably in the first couple of weeks.
Two practical rules:
- Measure in the evening. If a garment fits comfortably at your largest point in the day, it will fit at every other point. The reverse is not true.
- If you are still in the first two weeks postpartum, or still pregnant and buying ahead, measure and then go up a size. A garment that is slightly roomy and adjustable is useful. One that is slightly too tight is unwearable and usually cannot be returned once worn.
Reading the chart itself
Three rules that solve most confusion:
If you fall between two sizes, take the larger one. Almost all support garments have hook rows, Velcro panels or adjustable closures that let you tighten a slightly large garment. Nothing lets you loosen a small one.
If two of your measurements point to different sizes, follow the measurement the garment actually sits on. For a short belly band, that is your belly button measurement, not your hip. For a full-length faja, follow the hip.
Check whether the chart lists body measurements or garment measurements. A body measurement chart tells you what size body the garment is designed for. A garment measurement chart tells you the flat dimensions of the item itself, which will be smaller because the fabric stretches. Mixing these two up is a guaranteed wrong order. If the chart does not say, assume body measurements — that is the standard — but ask the seller if you are unsure.
Signs the size is wrong once it arrives
Put it on and sit down in a normal chair for five minutes. That is the real test, because standing still is not how you will wear it.
Too small if: it rolls or folds down at the top edge, it leaves deep marks that stay for more than a few minutes, it changes how you breathe, it will not close without significant force, or you feel any pinching or numbness.
Too large if: it slides downward when you walk, there is a visible gap at the top when you stand upright, or you are pulling the closure to its absolute tightest setting straight out of the packet — that leaves you no room to adjust later as your shape changes.
Fit beats compression, every time
Firmer is not better. A correctly sized garment at a moderate level of support will feel more comfortable, stay in place better and get worn far more often than a tight one that you take off after twenty minutes.
If something feels genuinely uncomfortable, restricts your breathing or causes any pain, take it off. And if you are recovering from surgery, including a caesarean, talk to your midwife, doctor or care provider before wearing any abdominal support — they will advise you on timing based on your own recovery.
This article is general guidance on measuring and sizing. It is not medical advice. Please speak with your care provider about what is appropriate for your individual situation.