Bra extenders can cure a lot of problems, but if not used correctly, can cause a lot more. Most common problems are back ride up, straps falling off the shoulders, sagging boobs and painful digging under the bust. I see it all the time.
Extenders come in a few styles, some with elastic and no adjustment, some with less elastic and limited adjustment, and some with no elastic and multiple adjustments. Usually I recommend the one with no elastic and multiple adjustments for best control.
A good use for extenders is when cups fit but the band is slightly tight. It is important to use the shortest additional length possible to be comfortable, while keeping the back down, the straps up and the bust contained.
The bad comes when a specific bra is not helped by making it looser. When an extender allows the back of the cup to come forward onto the breast, it can be painful, especially when the bra has bones or wires. If the extender causes the back straps to be too far apart, the straps will most likely fall off the shoulders. If the style of extenders or the amount of adjustment makes the bra too loose, the back will ride up or you’ll fall out of the bottom of the front.
Ugly is when everything goes wrong and the vicious cycle of corrections makes it worse. When a bra is too loose to start with or is extended much too far, the back rides up, the straps fall off, the bustline is down in front, the top center of the bra sticks out and the bra feels really tight under the bust. Tightening the straps to keep them from falling off and loosening the bra so it doesn’t feel tight causes the back to go higher, the front to go lower and the digging under the bust to be even more painful.
Extenders are not expensive and probably worth trying. Evaluate the situation based on the descriptions above, but know when to give up and buy a new bra. Comfort is worth everything!