The short explanation
A swelling on one side of the vaginal opening is often a Bartholin's cyst — a blocked gland that fills with fluid. Small cysts can be painless and may go on their own; if it becomes infected it can turn into an abscess, which is hot, red, very painful and makes sitting or walking hard. An abscess usually needs to be drained by a clinician. Warm baths or compresses can ease a small cyst, but do not try to squeeze or cut it yourself.
What depends on your situation
The parts of this that change from woman to woman. Uncertainty is stated, not hidden.
- Other lumps and sores on the vulva include ingrown hairs, boils, skin tags, genital warts and herpes sores, and, rarely, cancer of the vulva, which is more common after menopause. A lump that is painless, hard, growing, or comes with an itchy, white or thickened patch of skin needs examination.
- You can ask for a woman doctor and a chaperone for this examination.
What this answer cannot determine
The boundary of online education. These need a clinician who can see you.
- This cannot tell you what your lump is or whether it needs draining. Only an examination can.
Questions for your clinician
Take these with you. You can add any of them to an appointment card.
- Is this a Bartholin's cyst or something else?
- Does it need draining, and how is that done?
- What can I do if it comes back?
- Do I need any tests for infection?
When to seek help
Clinician-approved guidance for this topic. When in doubt, being seen is never the wrong choice.
- Get care the same day for a lump that is very painful, hot and red, or comes with fever.
- See a clinician within days for any new lump, sore or ulcer on the vulva.
- See a clinician within one to two weeks for a painless lump that is growing, or a patch of skin that has changed colour or texture, especially after menopause.
Sources
The evidence this explanation is built on.
- Bartholin's cyst NHS
- Vulval cancer NHS
Who wrote and reviewed this
Every AskHer answer names its author. A clinically reviewed answer also names the clinician who signed it off — if no clinician is named below, it has not been clinically reviewed.
- Author
- AskHer Editorial (AI-assisted draft) AskHer's editorial team — not an individual clinician Works in English, தமிழ், हिन्दी
- Clinical reviewer
- Nobody yet No clinician has signed this answer off, and no person on the editorial team has read it yet. That is what the “Written with AI assistance” label means. It is queued for an editor to read, and then for a clinician who works in this area. The sources it was drafted against are listed above.
- Review status
- Written with AI assistance — not yet reviewed by a person
- Last reviewed
- Not yet reviewed by a person
- Version
- 1
Correction history
Substantive changes are listed, not quietly edited away.
No corrections have been made since this answer was first published.
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