א אִשָּׁה שֶׁיֵּשׁ לָהּ וֶסֶת קָבוּעַ, אֵינָהּ צְרִיכָה בְּדִיקָה כְּלָל, לֹא לִפְנֵי תַּשְׁמִישׁ וְלֹא לְאַחַר תַּשְׁמִישׁ. וְאַדְּרַבָּה, אֵין לָהּ לִבְדֹּק בִּפְנֵי בַּעֲלָהּ בִּשְׁעַת תַּשְׁמִישׁ, כְּדֵי שֶׁלֹּא יְהֵא לִבּוֹ נוֹקְפוֹ. וְהָרַמְבַּ"ם זַ"ל מַצְרִיךְ לִבְדֹּק אַחַר תַּשְׁמִישׁ, הִיא בְּעֵד אֶחָד וְהוּא בְּעֵד אֶחָד, וְלִרְאוֹת בָּהֶם שֶׁמָּא רָאֲתָה דָּם בִּשְׁעַת תַּשְׁמִישׁ. וּלְדַעְתּוֹ, הַצְּנוּעוֹת בּוֹדְקוֹת עַצְמָן אַף קֹדֶם תַּשְׁמִישׁ. וּסְבָרָא הָרִאשׁוֹנָה הִיא עִקָּר, וְכֵן נָהֲגוּ. (רוֹקֵחַ וְהַגָּהוֹת מַיְמוֹנִי וְרֹב הַמּוֹרִים).
1 A woman that has a regular period cycle, does not need to check herself at all. Not before intercourse and not after having had intercourse. And on the contrary, she should not check in front of her husband at the time of intercourse, so that his heart will not push him away (i.e. eliminate his desire). And the Rambam, Z"L, requires her to check after intercourse, she with one inspection-cloth and he with one inspection-cloth, and to look in them perhaps, she saw blood at the time of intercourse, and according to him, the modest women check themselves also before intercourse. (And the first view is core, and such is the practice.)