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Did she have any associated Foul smelling discharge? If yes, it could be a Infection. If not, Release of white Mucus does not suggest Pregnancy
. It is the normal cleansing process of the vagina which removes the waste material from itself in the form or a white mucus.
If you have had Unprotected, wait for her next Period date, if she misses it, get a Urine Pregnancy Test done using a Early morning Urine sample to confirm it after a week of missing the Periods.
Good Luck, Take Care.