Islet autoantibody-positive patients had a lower BMI (median 22.9[21.1–25.7]) than autoantibody-negative patients (26.5[23.1–30.8]; P 0.002), more frequently required insulin during pregnancy (75 vs. 34%, P 0.0001), and more frequently had either HLA DRB1*03 (DR3) or HLA DRB1*04-DQB1*0302 (DR4-DQ8) haplotypes (77 vs. 39.4%;P 0.0001; Table 1).