CYP19A1 and Venous thrombosis: Therefore, the combination of GnRHa with LNG-IUD/aromatase inhibitors is a promising fertility-preserving alternative regimen for patients with endometrial carcinoma and atypical endometrial hyperplasia who are unsuitable for high-dose oral progestin, including those allergic to progestin or with body mass index ≥30 kg/m2, liver or renal dysfunction, hypercoagulable state, thrombophlebitis or thrombosis.