MMP3 and fetal growth restriction: After chondrogenic differentiation, compared with those in the control group, the cell viability of the IUGR group had no significant change (Fig. S2A), Safranin-O and Alcian blue staining showed that glycosaminoglycan contents in the alginate were decreased (P < 0.01, Fig. 1b–d), and the mRNA expression levels of the phenotypic genes COL2A1 and ACAN were significantly decreased (P < 0.01, Fig. 1e), but the mRNA expression levels of catabolic factors, including MMP3, MMP13, and ADAMTS5 were not changed (Fig. 1e).