Ubadah bin al-Walid bin Ubadah (may Allah have mercy on him) said: I said to Sayyidah al-Rubayyi' bint Mu'awwidh bin Afra (may Allah be pleased with her): "Tell me your story." She said: "I obtained a khul' from my husband, then came to Sayyiduna Umar (may Allah be pleased with him) and asked him what waiting period ('iddah) I had to observe. He said: 'You have no waiting period, unless he has had (marital) relations with you recently; in that case wait until you have one menstrual cycle.'" She said: "In this matter, in fact, the judgement of the Messenger of Allah (peace and blessings be upon him) concerning Maryam al-Maghaliyyah is followed. She was married to Thabit bin Qays bin Shammas, and on that basis she obtained a khul' from him."
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 21042