Table 2 Baseline characteristics of enrolled patients grouped by history of childbirth prior to surgery

Age (years)

28.01 (4.11)

26.41 (3.28)

31.64 (3.44)

0.000*

Height (m)

1.59 (0.05)

1.58 (0.05)

1.60 (0.05)

0.016*

Weight (kg)

50.08 (6.46)

49.14 (6.12)

52.21 (6.72)

0.000*

BMI

19.88 (2.26)

19.63 (2.18)

20.46 (2.35)

0.002*

Number of tumours removed

1.53 (0.95)

1.59 (1.02)

1.39(0.73)

0.048*

Diameter of the largest tumour (cm)

2.36 (1.04)

2.47 (1.06)

2.11 (0.97)

0.004*

Age at first birth (years)

28.73 (3.47)

29.78 (3.47)

26.35 (3.39)

0.000*

Interval between surgery and the first postoperative breastfeeding session (years)

2.79 (1.54)

2.84 (1.65)

2.69 (1.27)

0.362

Unilateral or bilateral breast surgery

0.074

Unilateral

267 (88.1%)

179 (77.5%)

88 (86.3%)

Bilateral

66 (11.9%)

52 (22.5%)

14 (13.7%)

Diameter of the largest tumour (cm)

0.077

≤ 3 cm

290 (87.1%)

196 (84.8%)

94 (92.2%)

>3 cm

43 (12.9%)

35 (15.2%)

8 (7.8%)