Is the lump more on one side, or is it in the middle?
Is the lump in the skin, or deeper inside (does it move with the skin, or does the skin move over it)? Thank you.
A lump to one side and toward the back of the vagina may be a Bartholin cyst, which forms when the opening to the Bartholin gland gets plugged. If it's not bothering you, it doesn't need treatment. It may become infected and get large and painful, in which case it would require drainage.
The lump may also be a skin lump, such as a sebaceous cyst. This forms when an oil gland gets plugged, and is very common.
Either lump could go away on its own, but may be more likely to stay.
It would require an exam to know the cause of your lump. As long as it's not bothersome, I think there is no hurry, but once you have a GP, I would make an appointment so you know for sure Best wishes.
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