1. Prenatal Diagnosis Center, Third Affiliated Hospital of Zhengzhou University (Henan Maternal and Child Health Care Hospital), Zhengzhou, Henan, P.R. China
2. Department of Galactophore, Third Affiliated Hospital of Zhengzhou University (Henan Maternal and Child Health Care Hospital), Zhengzhou, Henan, P.R. China
3. Department of Laboratory Medicine, Third Affiliated Hospital of Zhengzhou University (Henan Maternal and Child Health Care Hospital), Zhengzhou, Henan, P.R. China
4. Third Affiliated Hospital of Zhengzhou University (Henan Maternal and Child Health Care Hospital), Zhengzhou, Henan, P.R. China