The invention relates to a N-piperidin-4-yl derivative having the general Formula I or a pharmaceutically acceptable salt thereof, to pharmaceutical compositions comprising the same and to the use of said N-piperidin-4-yl derivatives for the treatment and prevention of endometriosis, for the treatment and prevention of pre-menopausal and peri-menopausal hormone-dependent breast cancer, for contraception, or for the treatment of uterine fibroids or other menstrual-related disorders.