Hello there.

Thanks for writing.

The reason behind the pain is engorgement of the breast.
When you tend to feed less from one side, milk gets collected inside leading to engorgement and pain. Breast become painful and hard so lesser milk comes out.
If left like this it might develop into an abscess.

Your wife should try feeding from the left side also.
Emptying the left breast would alleviate her pain.

If she has a lot of pain she can take paracetamol but should not stop feeding. The more she feeds, more milk will come out and pain would be relieved.

Tight breast support and fomentation (warm compresses) will help reduce the pain.

I hope I have answered your query.

Take care.

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