Reference for Yevamot 83:20

אמר רב ספרא אין בודקין את הנשואות שלא יתגנו על בעליהן ונבדקה בהלוכה

a woman who bears at seven months 'does give birth before the full number of months has been completed;<span class="x" onmousemove="('comment',' [H] (rt. [H] 'lop off') 'incomplete number of months'. ');">³⁰</span> for it is stated in Scripture, And it came to pass, after the cycles of days,'<span class="x" onmousemove="('comment',' I Sam. I, 20. E.V., When the time was come about. ');">³¹</span>

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