We found that in the insulin treatment group, there were higher values of progestational body mass index (BMI) (Z = −2.281, P = 0.023), higher incidence of diabetes (χ2 = 20.618, P < 0.001) and higher incidence of fatty liver (χ2 = 4.333, P = 0.037) than in the control group but also a higher pregnancy weight gain compliance rate (χ2 = 4.061, P = 0.044). Here, INS is linked to diabetes mellitus.