IGF1 and breast cancer: We found an overall increased breast cancer risk for IGF-1 or IGFBP-3 elevation, although it was not statistically significant (≥ median compared to <: IGF-1 OR = 1.37, 95% CI = 0.66–2.85; IGFBP-3 OR = 1.62, 95% CI = 0.81–3.24).