Responsa for Niddah 31:3

ה"ק

— It is this that was meant: And a priest came and gazed into it to ascertain whether she had aborted an inflated object or a premature child and, if some ground could be found for assuming that she aborted a premature child, to ascertain whether it was male or female. And if you prefer I might reply: Since weasels and martens are commonly found there they had certainly dragged it away.<span class="x" onmousemove="('comment',' Hence it is a case of a certainty against a certainty. ');">³</span>

Teshuvot Maharam