A monolithic pressure regulator may comprise a body comprising a base wall, an end wall, and a side wall, a cavity within the body, an input port in fluid communication with the cavity, an output port in fluid communication with the cavity, a first vesicle configured to regulate a flow of fluid through the input port into the cavity at a source pressure to exit through the output port at a regulated pressure, wherein the first vesicle comprises a first vesicle wall contiguous with a bulkhead and at least one of the base wall or the end wall.