Narada Purana (Jyotisha Selections) · by Vyasa
Chapter 2 · Signs, Planets, Birth
जातकम् १
कुर्याद्विलोमगो वापि स्वांशोक्तपरगैः समम् ।कुजेंदुहेतुकं स्त्रीणां प्रतिमासमिहार्तवम् ॥ ४१ ॥
In the full Narada Purana (Purva Bhaga) this is chapter 55, verse 41.
Or, placed the other way, a planet does the reverse. This is alike with its own and others' navamsha (one-ninth part of a sign). Mars and the Moon cause a woman's monthly flow, each month. (Our text is unclear here: the words about its own and others' navamsha.)
Simple meaning: Mars and the Moon cause the monthly cycle in women.
नेष्टस्थेज्येऽन्यथास्ते स्त्रीयुंक्तासन्नरेक्षिते ।
Bad planets with the 7th bring union in anger. Good planets bring union in love.
शुक्रार्केंदुजैः स्वांशस्थैरीज्य चांगत्रिकोणगे ।
Venus, Sun and Mercury in own navamsha, and Jupiter in the lagna or a luck house, give children.
अस्त्रेऽर्केंदो कुजार्की चेत्पुंस्त्रियोरामयप्रदौ ।
Mars and Saturn in the 7th from the Sun and Moon can bring a couple illness. Other placements may risk their lives.