Yes, Birch uses adhesives to glue the layers of their mattress together.
That being said, the Birch adhesives are water-based and have been approved as an accessory for use in GOTS-certified products.
Some mattress companies opt for needle-tufted designs, which eliminate the need for glues and other adhesives, but that does run the risk of some shifting across layers. There are certain pros and cons to each design strategy.
