Maternity leggings: over or under the bump, sizing and what lasts

Somewhere around 16 to 20 weeks your normal leggings start a slow slide. The waistband lands under the bump, rolls itself into a rope by lunchtime, and you spend the afternoon hitching. The hair bobble through the jeans buttonhole gave up a fortnight ago.

That's the week people search "maternity leggings" and land on a hundred pairs that all look the same in a photo. They aren't the same. Over or under the bump, the fabric, and the size you pick decide whether a pair lasts the whole pregnancy or ends up in the drawer by 30 weeks.

• Sizes S to XXL by dress size: S is 6 to 8, M 10 to 12, L 12 to 14, XL 14 to 16 and XXL 16 to 18. Between sizes, go up one.
• Two fabrics. Activ+ is a nylon blend that stays opaque when you squat. Comfort+ is 86% bamboo and the softer of the two. Both wash at 30 degrees.
• The panel goes over the bump. Pull it right up when you put them on; that's where it's made to sit.
• Medium is the size most people order.
• 30 day returns, and exchanges are welcome if the size isn't right.

Over the bump or under the bump maternity leggings?

Over-bump leggings have a tall stretch panel that goes up and over the whole bump. Under-bump leggings have a low, soft waistband that sits below it, like ordinary leggings with the fight taken out of the elastic.

Under the bump suits the early weeks and hot days: less fabric, and nothing on the bump at all. The catch is that as the bump grows, the waistband is sitting on the part of you that's moving, and that's where rolling down starts.

Over the bump is the one that lasts. With nothing sitting under the bump there's no waistband to roll, the panel gives light support across the bump rather than digging in under it, and it keeps stretching through the third trimester. It's also the pair you carry on wearing after the birth, because the panel sits high and soft over a tender tummy.

All of ours are over the bump, in two fabrics, and that's a choice rather than a gap. If you want one pair that works from the second trimester right through and out the other side, over the bump is the answer.

One reviewer at 30 weeks wrote: "Very comfortable, elastic leggings. Not see-through. Saving me from being uncomfortable at 30 weeks pregnant."

When should you switch to maternity leggings?

When the waistband of your normal pair sits under the bump and you're hitching. For most people that's the second trimester, but it's a comfort call, not a week. Soft, high waisted normal leggings might get you to 20 weeks; a firm gym pair will be digging in by 14.

Two things that don't work for long. Sizing up in normal leggings: the legs go baggy while the waist still cuts in. And rolling the waistband under the bump: it walks down as you do.

The sooner you switch, the more wear you get, because one over-bump pair carries you across trimesters. The panel stretches with you, so you're not rebuying at 30 weeks.

What size maternity leggings do I need?

Go by your dress size, not your bump. The panel stretches over any bump; the leg doesn't stretch as much, so the leg is the part you're sizing for.

Three rules, from the size guide and from the handful of low reviews we've had.

• Between two sizes, go up one. The Activ+ pair runs small and the Comfort+ runs slightly small; both product pages say so. The low reviews say the same thing from the other side: "Tight in the legs."
• Carry weight on your thighs, go up one. The leg is the close fitting part, not the waist.
• Don't size up for the bump. The panel stretches. Size up for it and you get baggy legs and a panel with nothing to hold.

If they're not right, exchange them within 30 days of your order, unused and unwashed with the tags on.

After the birth it changes: size by your dress size now, not before you were pregnant, and if in doubt, size up. Leggings that press on a tender tummy don't get worn.

Activ+ or Comfort+ bamboo, which pair for what?

Same panel, same sizes, different fabric. The honest split is exercise against everything else.

Seasons matter more than the old version of this post let on. In a cold February you want the Activ+ under a dress with proper socks; in a British July, the bamboo pair is the one people reach for, because the fibres move moisture away from the skin instead of trapping heat. The Comfort+ bamboo pair is on its own page.

One reviewer wrote of the Activ+: "The fabric is soft, stretchy and comfortably supportive." Another: "They are comfortable enough for home but smart enough to wear out."

Why maternity leggings roll down or go baggy

Rolling down is a waistband problem. Anything sitting under the bump, the bump pushes down on. Over-bump leggings don't have anything there, which is the whole point, but they only work if the panel is actually over the bump. Pull it right up when you put them on. Half up, it folds, and then it creeps.

Going baggy is a fabric problem. Cheap stretch stretches once and stays stretched, so by 30 weeks the knees have gone and the panel has nothing left to give. The panel on ours is a four way stretch that goes back to shape after it's been out to full stretch, which is why one pair keeps fitting across trimesters instead of sagging.

Washing matters more than people think. Both pairs wash at 30 degrees, and the label says that for a reason: hot washes are hard on stretch fabric.

The old version of this post had a comparison with ordinary leggings. Here's the honest version of it.

Maternity leggings for the gym, walking and pregnancy yoga

The NHS exercise in pregnancy page says keep up your normal activity for as long as you feel comfortable, that you should be able to hold a conversation while you exercise, and to tell the instructor you're pregnant. It also says not to lie flat on your back for long, particularly after 16 weeks.

For a class you want the Activ+ pair. It's the denser fabric and it stays opaque through squats and lunges, which is the thing most leggings fail at, and the panel stays put when you bend. The bamboo pair is fine for a walk; for anything with squats in it, take the Activ+.

If your ankles are swelling by the end of the day, leggings won't fix that. The NHS says to avoid standing for long periods, rest with your feet up when you can and keep taking walks, and a sudden increase in swelling is a call to your midwife. Our compression socks are the thing for the ankles.

Maternity leggings after the birth

Keep wearing the over-bump pair. The panel is soft and sits high, so for the first weeks it's the most comfortable thing you own, and after a caesarean it means nothing is pressing on the incision.

Postpartum leggings are the second stage. They're built for recovery rather than a bump: a higher waist with a U-shaped compression band across the tummy, and the front cut higher than the back so it clears the incision line. Compression waits until the wound has healed and you feel ready; if you're not sure, ask at your postnatal check or ask your midwife.

The full post on what to wear after a c-section has the week by week, knickers included.

One reviewer wrote: "Feels comfortable with a good firm hold around the tummy. Just what I needed."

Questions we get asked

Are maternity leggings worth it?

If you've reached the hitching stage, yes. One over-bump pair does the second and third trimesters and the weeks after the birth, which is more wear than most things you'll buy for pregnancy.

Are maternity leggings see-through when you squat?

The Activ+ aren't; the fabric is dense enough to stay opaque through squats, lunges and bending. The Comfort+ bamboo pair is opaque for everyday wear, but if you specifically want squat-proof, that's the Activ+.

Do maternity leggings run small?

Ours do, in the leg. Go by your dress size, and if you're between two sizes or carry weight on your thighs, take the bigger one. Don't size up for the bump.

How many pairs of maternity leggings do I need?

Two. One on, one in the wash, because a 30 degree wash doesn't dry overnight in a British autumn. Both pairs come as a twin pack for that reason.

What's the difference between maternity leggings and postpartum leggings?

Maternity leggings have a stretch panel that goes over a growing bump. Postpartum leggings have a higher waist and firmer compression across the tummy to support the muscles after the birth, with the front cut higher than the back to clear a c-section incision. Wear the maternity pair while you're pregnant and for the first weeks after, then move into the postpartum pair once you're healed and comfortable.

Can you wear maternity leggings in summer?

The bamboo pair, yes. The fibres are breathable and move moisture away from the skin instead of trapping heat, which is why it's the one people reach for in the warm months. The Activ+ is the heavier fabric and better for a cold morning.

If you're at the hitching stage, the maternity leggings collection has both fabrics side by side in every colour, and the size guide is one table that takes a minute before you order.