Overall, independent of subsequent breast cancer, the number of Wnt4-positive cells was significantly higher in nulliparous women (Groups 1 and 2) compared to women with early pregnancy (Groups 3 and 4, p = 0.0241, Mann-Whitney U test, Figure 4c), and compared to women with late pregnancy (Groups 5 and 6, p = 0.0374, Mann-Whitney U test, Figure 4d). This evidence concerns the gene WNT4 and breast cancer.