Keritot 25 - When Can One Bring An Offering Of Uncertainty
A person may donate an offering on uncertainty every day and any time that he wants - lest he has unknowingly transgressed - and it is called, "The guilt of the righteous" - this is the opinion of Rabbi Eliezer.
Bava ben Buta followed the opinion of Rabbi Eliezer and brought an offering of uncertainty every day, except after Yom Kippur. He said, "I swear by this Dwelling Place that if my colleagues allowed me, I would bring it - but I accede to their request not to bring it unless there is at least some possibility that I may have transgressed."
The Sages say that one brings an offering of uncertainty only when he might have transgressed a serious prohibition, for which he would otherwise have to bring a sin-offering. If one had an obligation to bring such offering, but Yom Kippur passed, he is now atoned for, provided that he repented and that he believes in the power of Yom Kuppur to atone for it.
A woman who possibly had to bring a bird as a sin offering, due to a doubtful birth, still needs to bring it after Yom Kippur, since this bird does not atone but rather allows her to go into the Temple and eat sacrifices. If one had an obligation for a definite sin-offering, Yom Kippur does not cancel that.
Art: Victor Lecomte - The Birth by Victor Lecomte