Sayyiduna Abdullah bin Amr (may Allah be pleased with him) narrates: The Prophet (peace and blessings be upon him) said: "Whoever touches his private part should perform ablution, and any woman who touches her private part should perform ablution."
Ahmad recorded it; its chain contains a narrator, Baqiyyah bin al-Walid, who narrated it with 'an'anah (using "from"), and he is a mudallis.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الطهارة / 1266