C9 and gestational diabetes: Nine proteins involved in the CCC signaling pathway were found to be significantly upregulated in all GDM samples when compared to controls (Figure 2a): SERPINA1 (by 2.1-fold, p ≤ 0.001), VWF (by 1.95-fold, p ≤ 0.01), SERPIND1 (by 4.36-fold, p ≤ 0.001), PLG (by 1.82-fold, p ≤ 0.001), C9 (by 2.22-fold, p ≤ 0.001), C7 (by 1.44-fold, p ≤ 0.001), C1QA (by 2.17-fold, p ≤ 0.01), F12 (by 1.67-fold, p ≤ 0.05) and SERPINF2 (by 1.74-fold, p ≤ 0.01).