Brief Answer:
Infection or mild abrasions are possible.

Detailed Answer:
Hi,

Thanks for posting your query.

Infections of the vagina, urinary tract and abrasions over the vulva, labia and the vaginal introitus, all can cause such irritation.

If it is urinary infection, you should have other associated symptoms like frequency, urgency, burning sensation, pain, fever etc.

If it is vaginitis, you may have itching, discharge, sometimes spotting and difficulty during intercourse, if you are sexually active.

Abrasions can result from trauma , constant friction of underclothing and rough intercourse.

Apart from these, occasional nerve twinges can also be felt as the vagina is a very sensitive and vascular part.

A clinical examination will suffice to clarify the issue.

If you wish to furnish any associated information, please do so that I can comment further.

Hope I have clarified your query. Please feel free contact if you need any more information. I will be happy to help.

regards,
Shanti.V.

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