This disclosure relates to a solid transdermal therapeutic system (Fig 1) with at least one single-layer matrix which comprises a matrix polymer supersaturated with gestodene or a gestodene ester, and ethinylestradiol, wherein gestodene is present in an amount of 2.1 mg and ethinylestradiol is present in an amount of 0.55 mg, and a removable protective film directly adjacent to the active-ingredient-containing matrix which is a siliconized or fluoropolymer-coated polyester removable film (release liner), the therapeutic system having a layer order starting, furthest removed from the skin, with a backing layer, an adhesive layer, a release layer, the active-ingredient-containing matrix and the removable protective film, and wherein if any fraction of gestodene or gestodene ester not dissolved in the matrix polymer crystallizes out, it crystallizes out in the form of amorphous or crystalline particles with an average diameter of at most 200 &mu；m, at the interface between removable protective film and active-ingredient-containing matrix or in the active-ingredient containing adhesive matrix, and on an area of less than 2% of the interface between the removable protective film and the active-ingredient containing matrix； and the matrix is free from solubility promoters, crystallization inhibitors and dispersants. The transdermal therapeutic system may contain a UV absorber.
