Letrozole combined with low dose highly purified human menopausal gonadotropin for ovulation induction in clomiphene citrate-resistant infertile women with polycystic ovary syndrome: a prospective study
Zhao Yue, Ruan Xiangyan, Li Yanglu, Du Juan, Alfred O. Mueck
Journal of Capital Medical University . 2016, (4): 431 -436 .  DOI: 10.3969/j.issn.1006-7795.2016.04.004