3Malmnas C. Induction of labour in the second and third trimester of pregnancy by a cervical balloon and intrauterine oxytocin infusion [J]. Acta Obstet Gynecol Scand. 1969. 48(3) : 61-62.
4A1-Shaikh GK, Wahabi HA, Fayed AA, et al. Factors associated with successful induction of labor [J]. Saudi Med J, 2012, 33(3): 298-303.
5Gelber S, Sciscione A. Mechanical methods of cervical ripening and labor induction [J]. Clin Obstet Gynecol, 2006, 49 (3) : 642-657.
6Margerison CE, Rehkopf D, Abrams B. Association of maternal gestational weight gain with short-and long- term maternal and child health outcomes [J]. Am J Obstet Gynecol, 2010, 202 (6) : 574.e 1-578.
7Monte S, Valenti O, Giorgio E, et al. Maternal weight gain during pregnancy and neonatal birth weight: a review of the literature[J]. J Prenat Med, 2011, 5 (2): 27-30.
8Crane JM, White J, Murphy P, et al. The effect of gestational weight gain by body mass index on maternal and neonatal outcomes [J-. J Obstet Gynaecol Can, 2009, 31 ( 1 ) : 28-35.
9Mandal D, Manda S, Rakshi A, et al. Maternal obesity and pregnancy outcome: a prospective analysis [J-. J Assoc Physicians India, 201l, 59(8): 486-489.
10Sadan O, Fleischfarb Z, Everon S, et al. Cord around the neck: should it be severed at delivery.9 A randomized controlled study [ J ]. Am J Perinatol, 2007, 24 ( 1 ) : 61-64.
