The Compendium of Caraka 4.8.40_2

4.8.40_2

tathā ca kurvatī śanaiḥ pūrvaṃ pravāheta, tato 'anantaraṃ balavattaram/tasyāṃ ca pravāhamāṇāyāṃ striyaḥ śabdaṃ kuryuḥ---'prajātā prajātā dhanyaṃ dhanyaṃ putram' iti /

And acting accordingly, she should bear down gently at first, then more forcefully thereafter. And while she is bearing down, the women should make the sound: 'Delivered, delivered of an auspicious, auspicious son!'