Young obese patients may benefit from GnRH-a long protocol contributing to higher implantation rate and live birth rate of fresh IVF-ET cycles oleh Qi Wan, Yue Qian, Ming-Jing Xia, Li Tan, Xing-Yu Lv, Xiang-Qian Meng, Yu-Bin Ding, Zhao-Hui Zhong, Li-Hong Geng