The invention provides a spinnerette assembly for forming hollow fibers. The spinnerette assembly contains an extrusion orifice and a fiber-forming material passage in communication with the extrusion orifice. A hollow needle extends through the extrusion orifice in a concentric manner to define an annular passage surrounding the needle. The fiber-forming material passage includes a fiber-forming material inlet port extending from a surface of the spinnerette assembly to an interior of the assembly and a transverse passage extending from the fiber-forming material port to the annular passage surrounding the needle. A bore forming fluid passage communicates with the interior of the needle.