Ibn al-Simt narrates: I heard Sayyiduna Bilal (may Allah be pleased with him) say: I said: "O Messenger of Allah, when I am intimate with my wife but we separate before ejaculation, shall I take a ritual bath (ghusl)?" The Prophet (peace and blessings be upon him) said: "Yes. I too have sometimes had intercourse with my wife without ejaculating, and we took a ritual bath."
Al-Tabarani recorded it in al-Mu'jam al-Awsat; its chain contains Muhammad bin Isma'il bin Ali al-Wasawisi, who is da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الطهارة / 1442