Chapter 108 — Ayodhya Kanda, Sarga 108

Valmiki Ramayana — Ayodhya Kanda

Verse 108.9

बीजमात्रं पिता जन्तोः शुक्रं शोणितमेव च। संयुक्तमृतुमन्मात्रा पुरुषस्येह जन्म तत्॥

bījamātraṃ pitā jantoḥ śukraṃ śoṇitameva ca| saṃyuktamṛtumanmātrā puruṣasyeha janma tat||

English Meaning

A father is merely an instrumental cause (touching the generation of his child). A father's semen coming in contact with a mother's blood, at the time befitting conception, a person is brought into being.

M.N. Dutt (1891–94, public domain)