Bhashya
अथ यस्य जायाम् आर्तवं विन्देत् ऋतुभावं प्राप्नुयात्-इत्येवमादिग्रन्थः ‘श्रीर्ह वा एषा स्त्रीणाम्’ इत्यतः पूर्वंद्रष्टव्यः, सामर्थ्यात् ।त्र्यहं कंसेन पिबेत्, अहतवासाश्चस्यात् ; नैनां स्नाताम् अस्नातां च वृषलो वृषली वा नो-पहन्यात् नोपस्पृशेत् ।त्रिरात्रान्ते त्रिरात्रव्रतसमाप्तौ आ-प्लुत्य स्नात्वा अहतवासाः स्यादिति व्यवहितेन संबन्धः ;ताम् आप्लुतां व्रीहीन् अवघातयेत् व्रीह्यवघाताय तामेवविनियुञ्ज्यात् ॥
In plain words
This passage — 'if a man's wife comes upon her monthly courses' — belongs, by the sense of it, just before the passage about a wife's glory, even though it is placed after it in the text. For three days she drinks from a bronze vessel and wears unwashed clothes; no one of low caste may touch her, bathed or not. When the three nights end, she bathes and puts on fresh garments — the text separates these two ideas, but they belong together. And once she has bathed, he sets her, and no one else, to pounding the rice.
Close to the Sanskrit
'Now, if a man's wife should come upon her monthly courses' — should attain the state of the fertile season — this passage, beginning thus, is to be understood as coming, by force of the sense, before the passage 'this indeed is the glory of women'; for three days she should drink from a bronze vessel, and she should be in fresh, unwashed garments; neither a low-caste man nor a low-caste woman should touch her — whether bathed or unbathed. 'At the end of the three nights' — at the completion of the three-night observance — 'having bathed' [means] having washed, [and] 'she should be in fresh garments' — this is the connection in sense, though separated [in the text]; her, thus bathed, he should set to pounding the rice — that is, he should assign her precisely to this task of pounding.