Reference for Niddah 17:1

קושי סמוך ללידה רחמנא טהריה

did not the All Merciful [it may be objected] ordain that [a flow of blood in] painful labour immediately before birth<span class="x" onmousemove="('comment',' The woman having had no relief from her pain between the appearance of the flow and birth (cf. prev. n. but one). ');">¹</span>

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