Lumps in the armpits during pregnancy may be caused by parastomia, enlarged lymph nodes and other reasons. 1. Associate Breasts: After pregnancy due to hormonal changes in the body, the breasts may become enlarged. Some pregnant women who have breasts are affected by hormones and also experience underarm lumps. This is due to the changes that occur after pregnancy, with the breast recovery after breastfeeding, underarm lumps will gradually disappear, pregnant women do not need to worry too much. 2. Enlarged lymph nodes: If there is local inflammation, tumors, etc., there will be swollen lymph nodes in the armpits. Pregnant women need to do further examination to clarify the cause, and then targeted treatment. If there is a lump in the armpit during pregnancy, you need to consult a doctor in time for an ultrasound examination to clarify the cause of the lump, and then deal with it under the guidance of the doctor.