Serum NfL (p=0.02), IL-6 (p < 0.0001), IL-12p40 (p < 0.0001), IL-15 (p=0.005), MIP-1α (p=0.007), TNFβ (p=0.03), and TNFα (p=0.0002) were increased in HF. Here, IL15 is linked to hydrops fetalis.