HIF1A and hydrops fetalis: Interestingly, the IL‐10 anti‐inflammatory signaling pathway, led by proteins IL‐10 and HMOX1 (heme oxygenase‐1), which serves as a downstream target of the transcription factor HIF‐1α (hypoxia‐inducible factor‐1α)—a key regulator of the body's response to hypoxia (Dunn et al. 2021)—was notably higher in HF (Figure 2B, top).