“…A total of 95.9% studies were prospective or retrospective cohorts and 4% were cross-sectional studies [20,21]. In addition, 17 (34.6%) studies used the GDM classification of group 1 [21,22,26,35,38,40,47,48,50,51,53,54,[59][60][61]64,67] and IADPSG; 7 (14.2%) group 2 [20,27,28,51,59,65,68], 3 (6.1%) group 3 [32,46,56], 1 (2%) group 4 [51], 19 (38.7%) group 5 [23][24][25]29,31,33,34,36,39,40,42,44,47,53,55,57,58,64,66], 6 (12.2%) group 6…”