To explore the risk factors of idiopathic granulomatous mastitis (IGM).

Totally 58 patients with IGM (IGM group) and 91 patients with benign breast disease (control group) in the Department of Breast Surgery, Wuhan Red Cross Hospital from January to December 2018 were enrolled for a retrospective study. The Pearson χ² test or Wilcoxon rank sum test was used to analyze the general data of the two groups. The variables with P<0.050 were processed by the binary logistic regression analysis to screen out the risk factors associated with IGM.

Univariate analysis showed that the following factors presented a significant difference between IGM group and control group: autoimmune diseases, chest impact, use of contraceptive drugs, number of full-term pregnancies, full-term pregnancy during the past five years, alternate breastfeeding and increased prolactin level (χ²= 4.180, 8.649, 4.650, -2.782, 19.607, 5.419, 10.740, all P<0.050). Multivariate analysis showed that autoimmune diseases, increased prolactin level, chest impact, full-term pregnancy during the past 5 years, use of contraceptive drugs and non-alternate breastfeeding were independent risk factors for IGM (OR=6.793, 4.553, 4.248, 3.657, 3.101, 2.492; 95%CI: 1.759-26.240, 1.519-13.648, 1.007-18.093, 1.652-8.095, 1.286-7.476, 1.146-5.419; P=0.005, 0.007, 0.047, 0.001, 0.012, 0.021).

For the patients with the above-mentioned IGM-related risk factors, the doctors should be aware of the high risk of IGM and provide certain prevention and intervention if necessary.