Midrash for Bava Batra 253:7
אי הכי תשב לזכר ולנקבה ולנדה מיבעי ליה קשיא
and, [consequently. he imposed a double] restriction.<span class="x" onmousemove="('comment',' That if a female as regards the unclean period, and that of a male regarding the clean period. In the case of circumcision, the restrictions of Sabbath observance also have been imposed. ');"><sup>22</sup></span> If so,<span class="x" onmousemove="('comment',' That, on account of the doubt, additional restrictions were imposed. ');"><sup>23</sup></span> it should have been [stated that] she should continue [in her uncleanness] for a male, and for a female, and for her menstruation!<span class="x" onmousemove="('comment',' Since it is also possible that the law of 'uncleanness of birth' is not applicable in such a doubtful case, the woman should be subject must only to the restrictions connected with the birth of a male and a female, but also to those of menstruation. The unclean period due to birth (fourteen for a female which include the seven for a male should not, accordingly, be followed by the clean period of twenty-six days (v. note 1, supra) during which she is regarded as clean even if blood had appeared, but by that of menstruation, I.e., let her be treated as if no birth at all had taken place and, consequently, if any blood appeared she should become menstrually unclean. ');"><sup>24</sup></span> — This is a difficulty.