Are these utterances considered one divorce or three, and what are the implications regarding the wife's ability to return?

If a man says to his wife, "You are divorced," one divorce (talaq (definition)) occurs. If he then says to her mother, "Your daughter is divorced," and then says the same to her father, intending to confirm the first divorce or merely to inform, a second or third divorce does not occur. Rather, it remains one divorce, and he can reconcile with her as long as she is within her waiting period (iddah (definition)).

However, if he intends to issue another divorce while she is still in her iddah, the majority of scholars hold that it occurs, because a woman undergoing a revocable divorce (iddah) is considered, in effect, still married. Some scholars, however, are of the view that it does not occur, because there is no divorce except after reconciliation (rujah) or a new marriage contract. This is the chosen opinion of Shaykh al-Islam Ibn Taymiyyah and Ibn Uthaymeen.

Therefore, as long as the husband uttered the second and third divorces during the iddah without reconciliation, only the first divorce occurs, and he can reconcile with his wife as long as she is within her iddah.