Mean galactosylation of IgG1 and IgG2 in cases and controls during pregnancy and postpartum. IgG1 (a) and IgG2 (b) galactosylation levels (in percentages) increase during pregnancy and decline postpartum. IgG1 and IgG2 galactosylation profiles of controls are at a significantly higher level than cases (P < 0.001, Linear Mixed Model at all timepoints). The vertical bars illustrate the 95% confidence intervals. Abbreviations: trim = trimester of pregnancy; wk = weeks; PP = postpartum; mon = months.