What are these lumps in my armpits?
Lumps in both armpits or axillae at the same time is usually due to axiliary extensions (or tails) of breast tissue.
As such they are typically more of an issue in advanced pregnancy and especially when your milk comes in. Characteristically they will be less apparent when your breasts are empty of obvious milk at the end of a breastfeeding session. They can get large and uncomfortable. A lump in one axilla only may not be due to breast tissue but may indicate infection in the skin (such as can occur with shaving or antiperspirants), cysts or enlarged lymph nodes. An enlarged lymph node can be secondary to infections or malignancy. Breast cancer is infrequently diagnosis in pregnancy. Breast cancer can enlarge the armpit lymph nodes even when the breast itself seems perfectly normal.
What can be done?
Breast self-examination. Advise me (Dr Sykes) as soon as possible so I can establish the cause. Sometimes a breast and / or axilla ultrasound scan is needed. Sometimes even a consultation with a breast surgeon and biopsy is required. Axillary tails of breast tissue will settle and not be apart or be of minimal size when not pregnant. They will though recur with the next pregnancy. If this will be a problem for you can have the extra breast tissue removed surgically by a breast surgeon between pregnancies. If the lump is due to an infection then antibiotics may be needed.