Figure 2 illustrates that the breast cancer risk in women with non-insulin-treated and insulin-treated GDM equaled the risk in the reference group of women without GDM; the aHRs reached 0.96 (95% CI 0.80–1.15) and 1.55 (95% CI 0.86–2.30) respectively, when analyzing data in women without subsequent diabetes. Here, INS is linked to diabetes mellitus.