Ubaydullah bin Abdullah bin Utbah (may Allah have mercy on him) narrated that his father wrote to Abdullah bin al-Arqam al-Zuhri (may Allah be pleased with him), instructing him to go to Subay'ah bint al-Harith al-Aslamiyyah (may Allah be pleased with her) and ask her about her story, and about what the Messenger of Allah (peace and blessings be upon him) had said to her when she delivered her pregnancy. So Umar bin Abdullah wrote to Abdullah bin Utbah, informing him that Subay'ah (may Allah be pleased with her) had told him that she was married to Sa'd bin Khawlah (may Allah be pleased with him), who was from Banu Amir and was among those who took part in Badr. He died during the Farewell Hajj while she was pregnant, and she gave birth after his death. When she had recovered from her postnatal bleeding (nifas), she adorned herself for those who might propose. Then a man of Banu Abd al-Dar, Abu al-Sanabil bin Ba'kak, came in to her and said to her: Why do I see you adorned? Perhaps you want to marry. By Allah, you cannot marry until four months and ten days have passed over you. Sayyidah Subay'ah (may Allah be pleased with her) said: When he said that to me, I gathered my clothes about me until evening came, then I came to the Messenger of Allah (peace and blessings be upon him) and asked him about that, "and he gave me the ruling that I had come out of my waiting period on the day I gave birth, and he told me to marry if I wished."
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 21119