Methods: We review pertinent publications that were retrieved by a selective search of the literature from 1966 to 2012, including current meta-analyses from the Cochrane database and the guidelines of German and foreign obstetric societies.
Methods: We review pertinent publications that were retrievedby a selective search of the literature from 1966 to2012, including current meta-analyses from the Cochranedatabase and the guidelines of German and foreign obstetricsocieties.