Astanga Hrudaya
पूर्णषोडशवर्षा स्त्री पूर्णविंशेन सङ्गता। शुद्धे गर्भाशये मार्गे रक्ते शुक्रेऽनिले हृदि॥८॥
The women, who has completed sixteen years of age, mating with a man who has completed twenty years, the uterus, the channels, the blood (menstrual), semen, vata and hrdaya (the mind, in this context) all being pure (unvitiated),
english translation