Narada Purana (Jyotisha Selections) · by Vyasa
Chapter 7 · Samskara Muhurtas
संस्कारमुहूर्ताः
परिघस्य च पूर्वार्द्धं व्यतीपाते सवैधृतौ ।संध्यासूपप्लवे विष्ट्यामशुभं प्रथमार्त्तवम् ॥ ३१३ ॥
In the full Narada Purana (Purva Bhaga) this is chapter 56, verse 313.
A girl's first period is bad in these times. Bad are the first half of Parigha, Vyatipata (a bad Sun and Moon yoga) and Vaidhriti. So are the twilights, an eclipse and vishti (bad half of a moon day).
Simple meaning: A girl's first period at bad almanac times, twilight or an eclipse is seen as a bad sign.
रुग्णा पतिप्रिया दुःखा पुत्रिणी भोगनी तथा ।
The weekday of a girl's first period shows what her later life may be like.
यामाग्निरौद्रभाग्याहिद्वीशेंद्रादिह्युपद्विषाः ।
A first period on some stars or in some months is not good.
भद्रा च संक्रमो निद्रा रात्रिश्चंद्रार्कयोर्ग्रहः ।
A first period at these bad times may lead to a woman who goes astray.