To evaluate the efficacy of ductal probing in treating milk stasis and the possible influencing factors.

A total of 2 544 patients with milk stasis in Haidian Maternal and Child Health Hospital from January 2012 to May 2016 were enrolled in this prospective study. They were divided into the study group (n=1 159)and the control group (n=1 385) using a random number table method. The patients in study group were treated by ductal probing and the patients in control group received comprehensive physiotherapy(including local massage, semiconductor laser physical therapy, electric breast pump sucking and external application with 50% magnesium sulfate for 30 min). The patients were followed up for 1 month. The efficacy and recurrence rate were compared between two groups. According to the course of milk stasis, the distance from the nipple to the lump and the lump diameter, all patients in study group were subdivided to compare the efficacy of ductal probing among subgroups. The recurrence rate was compared between two groups using χ² test. The non-parametric test was used to compare the treatment outcome. Two groups were compared using the Wilcoxon test, and three groups were compared using the Kruskal-Wallis test.

After the treatment, there were 847 patients cured, 156 improved, 73 with clinical response, 65 with no response, and 18 with disease progression in the study group, 441, 312, 291, 308 and 33 in control group. The efficacy of ductal probing showed a significant difference (Z=-20.75, P<0.001). The difference in the recurrence rate between two groups was not statistically significant [14.6% (169/1 159) vs 14.0% (194/1 385), χ²=0.17, P=0.680]. Subgroup analysis showed that the efficacy of ductal probing was significantly different among the subgroups with different courses (<2 d, 2~3 d and >3 d) and different distance from the nipple to the lump (< 3 cm, 3~5 cm and >5 cm) (Z=116.14, P<0.001; Z=198.77, P<0.001). The efficacy of ductal probing showed no significant difference between the patients with the lump ≤5 cm and the patients with the lump >5 cm (Z=-1.00, P=0.317).

Compared with mammary physiotherapy, ductal probing is effective in patients with milk stasis, worthy of clinical application. The outcome of this operation is related to the disease course and the distance from the nipple to the lump, irrelevant of the lump diameter.