Disclosed is the use of a compound of formula (I) e.g. 17-acetoxy-11-(4-N,N-dimethylaminophenyl)-19-norpregna-4,9-dien-3,20-dione or a pharmaceutically acceptable salt, hydrate or solvate thereof, wherein: X represents an alkyl, alkenyl, alkynyl, hydrogen, halo, monoalkylamino or dialkylamino； R1 represents -=O, =NOH or =NO-methyl； R2 represents a hydrogen or acetyl； and R3 represents methyloxy, formyloxy, acetoxy, acyloxy, S-alkoxy, acetyltheonyl, glycimate, vinyl ether, acethyloxymethyl, methyl carbonate, halogens, methyl, hydroxy, or ethyloxy at a dose of about 12.5mg to about 25mg for the manufacture of a medicament to be administered to a female for a period beginning during the luteal phase of the female's menstrual cycle and lasting at least four months, for the long term treatment of an estrogen dependent condition selected from the group consisting of endometriosis, uterine fibroids and dysfunctional uterine bleeding.
