Hi,
No, it would not of itself be grounds for an annulment. Annulments are based on the circumstances that surrounded the wedding. Were both parties making free choices? How psychologically mature were they. Was either of them with-holding information that would cause the other to not go through with the wedding? Were either of them still in their teens?
These and other questions like them have to do with how capable they were of making a mature, knowledgeable free choice.
Fr. Vincent Serpa, O.P.