1. Reproductive Physiology Laboratory (X.X., X.C., H.C., C.S., S.G., S.Z., B.H., J.W.), National Research Institute for Family Planning, Beijing 100081, People's Republic of China
2. Graduate School (X.C., H.C., S.G.), Peking Union Medical College, Beijing 100730, People's Republic of China
3. Hebei Medical University (Y.L.), Shijiazhuang 050017, People's Republic of China