Skip to main content

Table 1 Comparisons of characteristics between parous and nulliparous women

From: Towards defining morphologic parameters of normal parous and nulliparous breast tissues by artificial intelligence

Variable N Parous women (N = 180) N Nulliparous women (N = 545) p value
Age of donation (years) 180 35 (22, 45) 545 25 (18, 45)  < 0.001
Ethnicity (Hispanic/Latino) 180 13 (7.2%) 544 39 (7.2%) 1.00
Race 180   545   0.10
 Caucasian   149 (82.8%)   479 (87.9%)  
 African American   31 (17.2%)   66 (12.1%)  
BMI 180 27.0 (14.3, 62.9) 545 25.4 (13.3, 63.2) 0.062
Current smoking 166 5 (3.0%) 530 31 (5.8%) 0.17
Current drinking 179 125 (69.8%) 542 394 (72.7%) 0.50
Age at first period (years) 180 12.5 (8, 19) 545 12 (8, 18) 0.44
Menstrual status 180   544   0.82
 Pre-menopausal   173 (96.1%)   525 (96.5%)  
 Post-menopausal   4 (2.2%)   11 (2.0%)  
 Uterine ablation   3 (1.7%)   8 (1.5%)  
Number of live births 180   N/A N/A N/A
 1   61 (33.9%)    
 2   83 (46.1%)    
 3   31 (17.2%)    
 4   4 (2.2%)    
 5   1 (0.6%)    
Time since last birth (years) 180 4.0 (0.1, 11.0) N/A N/A N/A
Age at first birth (years) 180 28 (16, 41) N/A N/A N/A
History of breastfeeding 180 156 (86.7%) N/A N/A N/A
 Total months breastfeeding 156 9 (1, 90) N/A N/A N/A
Total months breastfeeding (with no breastfeeding considered to be 0 months) 180 6 (0, 90) N/A N/A N/A
Relative with breast/ovarian cancer 168 104 (61.9%) 511 252 (49.3%) 0.006
  1. The sample median (minimum, maximum) is given for continuous variables. p values result from a Wilcoxon rank sum test (continuous variables) or Fisher’s exact test (categorical variables)