SB 3.31.8

ulbena saṁvṛtas tasminn
 antraiś ca bahir āvṛtaḥ
āste kṛtvā śiraḥ kukṣau
 bhugna-pṛṣṭha-śirodharaḥ
Synonyms: 
ulbena — by the amnion; saṁvṛtaḥ — enclosed; tasmin — in that place; antraiḥ — by the intestines; ca — and; bahiḥ — outside; āvṛtaḥ — covered; āste — he lies; kṛtvā — having put; śiraḥ — the head; kukṣau — towards the belly; bhugna — bent; pṛṣṭha — back; śiraḥ-dharaḥ — neck.
Translation: 
Placed within the amnion and covered outside by the intestines, the child remains lying on one side of the abdomen, his head turned towards his belly and his back and neck arched like a bow.
Purport: 

If a grown man were put into such a condition as the child within the abdomen, completely entangled in all respects, it would be impossible for him to live even for a few seconds. Unfortunately, we forget all these sufferings and try to be happy in this life, not caring for the liberation of the soul from the entanglement of birth and death. It is an unfortunate civilization in which these matters are not plainly discussed to make people understand the precarious condition of material existence.