Brihat Parashara Hora Shastra
पुत्रस्थानं गते जीवे तदीशे भृगुसंयुते । द्वात्रिंशे च त्रयस्त्रिंशे वत्सरे पुत्रसम्भवः ॥ १८॥
If Putr is occupied by Guru, while its Lord is with Śukr, one will obtain an offspring in his 32nd, or 33rd year.
english translation
putrasthAnaM gate jIve tadIze bhRgusaMyute । dvAtriMze ca trayastriMze vatsare putrasambhavaH ॥ 18॥
hk transliteration by Sanscript