CRP and hydrops fetalis: Thus, based on a predefined decision tree (Supplementary Figure S1), no significant causal effects between CRP (MR Egger; OR = 0.93, 95% CI = 0.84–1.02, p = 0.15) and fibrinogen (weighted median; OR = 0.94, 95% CI = 0.55–1.58, p = 0.80) and HF risk were observed (Table 1).