Commentary for Avodah Zarah 82:15

Yes, I know that this source is a bit gross and quite strange as well. Why does the priest need to know if it is male or female? While it is true that there are different periods of purity and impurity for male or female births (see Leviticus 12), is this slave Jewish such that she would observe these laws? Why doesn’t the priest know that he should not look into the pit to see because that would make him impure? In any case, there seems to have definitely been a source of impurity placed into the pit. The doubt is over whether it is still there. And again, a doubt does seem to set aside a certainty.