Hi and thanks for your question. If HIV was transmitted at the time of contact, then everyone is considered to have antibodies to HIV detectable in their blood by 12 weeks post contact.  That is why testing at 3 months is now considered to cover the window period.  There are still many information sites online that have the 6 month window period listed.  If you find that you are worrying a lot about this, then testing again at 6 months post contact can be reassuring. Hope this helps. Health  Nurse