Sayyiduna Uthman bin Abi al-As (may Allah be pleased with him) narrates: When the Prophet (peace and blessings be upon him) sent me to the tribe of Thaqif, he said to me: "O Uthman, keep the prayer short, and lead the people in prayer according to the weakest among them, for among the people are the weak, those with work to attend to, pregnant women and nursing women."
(Allamah al-Haythami says:) I say: This hadith is in the Sahih, except that these words are not in it: "the nursing and the pregnant women".
Al-Tabarani recorded it in al-Mu'jam al-Awsat, and its narrators have been declared trustworthy.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصلاة / 2377