Fit Problem: Cup fabric wrinkles when still

The short answer: Too much cup for your tissue, or a projected cup on a shallow shape. Go down a cup letter or pick a shallower profile like a t-shirt bra. Wrinkles only when leaning are normal.

Wrinkles across a cup that should lie smooth mean unfilled volume, and where the wrinkle sits maps the mismatch. Wrinkling at the bottom of the cup means the cup is deeper than your projection; your tissue spreads wider and shallower than the pattern assumes. Wrinkling at the top is ordinary gaping territory. Wrinkles everywhere mean a whole letter too much cup.

Shallow-projection shapes fight bottom wrinkles constantly in deep-cup brands, and the solution is profile, not letters: molded t-shirt cups and brands cut for shallow roots (many Asian-market and US mall brands) hold a wide, shallow curve that seamed deep-cup UK patterns do not. The reverse shopper, projected tissue in shallow mall cups, meets spillage instead; brands really do pick a body and cut for it.

Unlined and stretch-fabric cups forgive small mismatches that foam announces, which makes them the practical choice while your size settles, after weight change, postpartum, or between sister sizes.