The knit choice is made early and it is expensive to change later. These four cover almost everything in a babywear range, and they are not interchangeable.
Interlock
What it is: two smooth knitted faces joined back to back. There is no wrong side and no curl at a raw edge.
Weight: typically 180–240 gsm.
Why it dominates babywear: it does not curl, it does not twist after washing, and it cuts and sews predictably. That makes it the default for bodysuits, sleepers, rompers, bibs and pants — the pieces that have to hold their shape through a hundred washes and a lot of pulling.
Where it disappoints: it is not a fashion fabric. It has no drape story and no surface interest. A range built entirely from interlock is functional and slightly flat.
Jersey (single knit)
What it is: a single knitted face with a technical back. Lighter, drapier, and it curls at an unfinished edge.
Weight: typically 140–190 gsm.
Where it belongs: warm-weather pieces, dresses, and anywhere the garment needs to fall rather than stand. Bamboo viscose jersey takes this further — it is denser and more fluid, with a soft sheen.
Where it disappoints: it is less forgiving in construction. Curling edges mean hems and necklines need ribbing or a folded finish, and thin jersey shows every construction shortcut.
French terry
What it is: a knitted loop fabric — smooth on the face, with loops left on the back. Brushed variants raise those loops into a soft pile.
Weight: typically 220–320 gsm, and it is the heaviest of the four.
Where it belongs: sweatshirts, hoodies, joggers, bubble rompers, dungarees, shorts — the pieces that are worn as outerwear and take abrasion.
Where it disappoints: it is too warm and too heavy for a newborn's base layer, and at the top of the weight range it can overwhelm a small silhouette. A bubble romper in 320 gsm terry reads as bulky rather than generous.
Pointelle and jacquard
What it is: a fine-gauge knit with deliberate eyelet columns or a pattern worked into the structure itself, rather than printed on top.
Weight: typically 150–190 gsm.
Where it belongs: newborn layering — bodysuits, pants, knot hats, receiving blankets. The open structure breathes harder than plain jersey at the same weight, which is the whole point.
Where it disappoints: the eyelet structure is a snag risk around fasteners and it is slower to sew, so it costs more per piece than an equivalent-weight interlock.
A range that uses all four
- Newborn base layer: pointelle bodysuit and pants. Breathable, light, layered.
- Everyday core: interlock bodysuits, sleepers and bibs. The volume drivers, and the pieces that get reordered.
- Outerwear and play: French terry sweatshirts, hoodies, joggers, bubble rompers.
- Warm-weather and gifting: bamboo or cotton jersey dresses and two-piece sets.
The test that matters more than the specification
Ask for the shrinkage and colour-fastness behaviour of the proposed quality before you approve the fit. A garment that fits on the sample table and not after the first wash has not been properly specified, and no amount of inspection at the end of the line will fix it.
"100% cotton" describes the fibre, not the fabric. A 150 gsm single jersey and a 300 gsm brushed French terry can both be 100% cotton and behave nothing alike. Always specify weight and structure alongside composition.