IGF1 and hydrops fetalis: In addition, individuals with intermediate IGF-1 levels had a lower risk of developing HF [risk ratio (RR) 0.78; 95% CI 0.74–0.83; p < 0.01] and HF-related mortality (RR 0.98; 95% CI 0.97, 0.99; p < 0.01) compared to those with low IGF-1 levels, suggesting a protective role for maintaining adequate IGF-1 levels.