Reference for Niddah 75:22

מאי דעתייכו משום נפלים אין קושי לנפלים

It was taught: R. Meir used to say. A woman may sometimes bleed<span class="x" onmousemove="('comment',' Lit., 'be in protracted labour', labour extending over a part of the period. ');">¹⁹</span>

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