Brief Answer:
Need more information

Detailed Answer:
Hello and welcome to ask a doctor service. I have gone through your query and noted your concern.

I need to gather more information from you in order to be able to help you better.
Do you have any associated symptoms like pain? vulval itching? burning?
Are you sexually active? If yes, with one or multiple partners?when was the last time you had sexual contact? and whether it was protected or unprotected?
Is there any vaginal discharge? vulval sores?

Hope to assist you further once I get the required information..

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Brief Answer:
Regarding genital symptoms

Detailed Answer:
Hi.
Along with chlamydia screening I also suggest screening for other infections like Gonorrhea, Genital Herpes and Syphilis. Swelling and redness on vaginal lips could possibly be due to an STI like Genital Herpes, Syphilis, Gonorrhea and Chlamydia. Genital herpes presents with genital sores along with swelling and burning sensation whereas Syphilis is usually a painless sore which may go unnoticed therefore it may manifest only on tests and may coexist with other STDs like genital herpes So, in my view you should undergo a full spectrum STDs screening if there is a history of risk exposure.
Take care. Let me know if you need any more assistance.

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