“…There were 86 included studies for SGA [ 7 , 9 , 37 , 39 , 47 , 51 , 53 - 55 , 57 , 59 - 61 , 64 - 67 , 69 , 74 , 76 - 141 ], reporting on 382,005 women (20339 cases of SGA, incidence 5.32%). Among these studies, there were 61 cohort studies and 25 case control studies [ 53 , 55 , 76 , 77 , 82 - 85 , 88 , 89 , 94 , 96 , 97 , 104 , 113 , 116 , 119 , 123 - 125 , 130 , 131 , 133 , 135 , 140 ]. Thirty-one studies were prospective, 17 retrospective and 38 of unclear design.…”