The Compendium of Bheḷa 4.4.31

4.4.31

atrāha---kiṃnu[tu]garbho[garvo] māturudarastho ' śnāti[māturastho] na veti | atrocyate nāśnāti | yadi hy aśnīyāt syādasya[asyā puruṣa] purīṣamatītakālaṃ, na cedamasti[cedasi] | kathaṃ tarhi? nābhyāṃ nāḍī pratiṣṭhitā tasyāmaparā māturhṛdayamāśritā tayā māturannaraso ' bhivahan garbhaṃ prīṇayatyabhivardhayati | tad yathā kulyāḥ kedāramabhisaṃśrayantyo bhāvayanti tadvat ||

On this he asked: Does the fetus residing in the mother's womb eat or not? On this it is said: It does not eat. For if it ate, it would have feces whose time has passed, and this is not the case. How then? A vessel is attached to the navel, and another to it is connected to the mother's heart; through it, carrying the mother's food-juice, it nourishes and enlarges the fetus. Just as watercourses flowing toward a field saturate it, even so.