SHBG and gestational diabetes: Insulin resistance index (HOMA-IR) (HOMA-IR = FINS×FPG/22.5) and pancreatic β-cell function index (HOMA-β) (HOMA-β= 20×FINS/(FPG-3.5)) were used to compare various criteria including the number of pregnancies, FPG, HbA1c, FINS, SHBG, body mass index (BMI), and IGF-1 between pregnant women in the GDM group and the control group.