The reasons for breast swelling and pain when menstruation is delayed for 3 days are as follows: 1. Simply delaying menstruation for 3 days is a normal phenomenon. Breast swelling and pain is a relatively common menstrual syndrome, and if the pain symptom is not serious, there is no need to carry out special treatment. If the pain symptoms are serious, you can consider appropriate hot compresses or breast massage to relieve the symptoms, if you have breast swelling and pain symptoms, breast swelling and pain symptoms worsened during menstruation, there may be breast hyperplasia, breast fibroids and other diseases, you can do mammogram or ultrasound and other tests to clarify the diagnosis. 2, such as normal menstrual cycle, menstrual period without breast swelling and pain manifestations, the sudden emergence of this symptom, more than Considering that it may be a recent period of excessive stress, emotional fluctuations are too obvious, overthinking and so on, resulting in stagnation of liver qi, and caused by menstruation and breast distension and pain symptoms, you can consider taking the flavored Easy Pill to regulate.