RETN and gestational diabetes: Elevated serum leptin (OR = 1.166; CI = 1.104–1.233; p < 0.0001), resistin (OR = 1.772; CI = 1.432–2.192; p < 0.0001) and visfatin (OR = 1.342; CI = 1.185–1.518; p < 0.0001) were associated with GDM.