Rig Veda 10.184

May Vishnu form and mould the womb, may Tvashtar duly shape the forms, Prajapati infuse the stream, and Dhatar lay the germ for thee.

O Sinivali, set the germ, set thou the germ, Sarasvati: May the Twain Gods bestow the germ, the Asvins crowned with lotuses.

That which the Asvins Twain rub forth with the attrition-sticks of gold,- That germ of thine we invocate, that in the tenth month thou mayst bear.