
I know several women who suffer from the same. As far as I know it is quite common and nothing to worry about. The doctor will make a small cut and release the fluid inside. Often the cause is an ingrown hair due to shaving that particular area. You will be out of the office in no time, the only uncomfortable part could be the fact that a doctor will be fumbling around in your groin area, though I personally never care about that.
There is also an old fashion remedy to this type of cyst.
If you put a very warm hard boiled egg with shell on it for 10 minutes , in most cases it will loosen the “head” and the fluid will pour out.
It’s not a joke that’s how it was solved in the past in some asian countries.
Otherwise what lindathepin said is correct these days