Intravaginal Misoprostol for Cervical Ripening and Labor Induction in Nulliparous Women: A Double-blinded, Prospective Randomized Controlled Study oleh Yu Zhang, Hao-Ping Zhu, Jian-Xia Fan, Hong Yu, Li-Zhou Sun, Lian Chen, Qing Chang, Nai-Qing Zhao, Wen Di