Immunohistochemical staining of Syndecan 3 in uterine tissue at different stages of pregnancy. (A) Non-pregnant (group 1), (B) term-pregnant (group 2), (C) women in normal labour (group 3), (D) in prolonged labour (group 4), (E) in normal labour, magnification 1 × 400 with oil, (F) negative control. Magnification in A, B, C, D and F is 1 × 200. Positive staining is brown. The grading of staining is presented in Table 2.