Some women will have breast swelling and pain before menstruation, if there is pain but not menstruation for a long time, mostly due to menstrual disorders, pregnancy and normal conditions, as follows: 1, menstrual disorders: due to endocrine disorders as well as changes in the body of estrogen, progesterone, prompting the development of mammary gland follicles, so you will feel the swelling of the breasts; 2, pregnancy: if you have sexual intercourse and do not contraceptives, the swelling of the breasts and menstruation stops, then the pregnancy. Pregnancy: if you have sex and no contraception, and your period stops, then you are pregnant. If your period stops for more than a week and your breasts are swollen, you should buy a pregnancy test; 3. Normal: a week of early or delayed menstruation is normal, and it can be accompanied by breast swelling and pain, so you don’t need to be too nervous and anxious, and you should pay attention to using loose underwear and avoiding exertion, and you can just observe it for a while.