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and doxycycline are potent antibiotics and need to be taken in the physician supervision.
They are not effective for Candida infection. The infection can take place through sexual intercourse.
May be you were treated for it but it was never cured. You should not conceive during this treatment.
You need to consult a gynecologist for local examination and get a urine culture and CBC, high vaginal swab- gram stain & culture and then decide about management.
Wish you a great health!