Risk Factors for Preterm Birth in Five Maternal and Child Health Hospitals in Beijing

• Yun-Ping Zhang ,

  * E-mail: ypzhang7090@yahoo.com.cn

  Affiliation Department of Gynecology and Obstetrics, Maternal and Child Health Hospital, Haidian District, Beijing, China

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• Xiao-Hong Liu,

  Affiliation Department of Gynecology and Obstetrics, Maternal and Child Health Hospital, Haidian District, Beijing, China

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• Su-Hong Gao,

  Affiliation Department of Gynecology and Obstetrics, Maternal and Child Health Hospital, Haidian District, Beijing, China

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• Jia-Mei Wang,

  Affiliation Department of Gynecology and Obstetrics, Maternal and Child Health Hospital, Haidian District, Beijing, China

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• Yue-Shan Gu,

  Affiliation Department of Breast Surgery, Maternal and Child Health Hospital, Tongzhou District, Beijing, China

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• Jiu-Yue Zhang,

  Affiliation Department of Anesthesiology, Maternal and Child Health Hospital, Shunyi District, Beijing, China

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• Xia Zhou,

  Affiliation Department of Pediatrics, Maternal and Child Health Hospital, Changping District, Beijing, China

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• Qing-Xia Li

  Affiliation Department of Gynecology and Obstetrics, Maternal and Child Health Hospital, Daxing District, Beijing, China

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