مُوَطَّأُ مَالِكٍ
Muwatta Malik 132
Purity
وَحَدَّثَنِي عَنْ مَالِكٍ، أَنَّهُ سَأَلَ ابْنَ شِهَابٍ عَنِ الْمَرْأَةِ الْحَامِلِ، تَرَى الدَّمَ قَالَ تَكُفُّ عَنِ الصَّلاَةِ، . قَالَ يَحْيَى قَالَ مَالِكٌ وَذَلِكَ الأَمْرُ عِنْدَنَا .
Yahya related to me from Malik that he asked Ibn Shihab about a pregnant woman who noticed bleeding. Ibn Shihab replied, "She refrains from prayer." Yahya said that Malik said, "That is what is done in our community."
Arabic/English book reference: Book 2, Hadith 103