"Dany touched the soft swell of her belly. Sweat beaded her skin and trickled down her brow. She could feel the old women watching her, the ancient crones of Vaes Dothrak, with eyes that shone dark as polished flint in their wrinkled faces. She must not flinch or look afraid. I am the blood of the dragon, she told herself as she took the stallion's heart in both hands, lifted it to her mouth, and plunged her teeth into the tough, stringy flesh.
Warm blood filled her mouth and ran down over her chin. The taste threatened to gag her, but she made herself chew and swallow. The heart of a stallion would make her son strong and swift and fearless, or so the Dothraki believed, but only if the mother could eat it all. If she choked on the blood or retched up the flesh, the omens were less favorable; the child might be stillborn, or come forth weak, deformed, or female.
Her handmaids had helped her ready herself for the ceremony. Despite the tender mother's stomach that had afflicted her these past two moons, Dany had dined on bowls of half-clotted blood to accustom herself to the taste, and Irri made her chew strips of dried horseflesh until her jaws were aching. She had starved herself for a day and a night before the ceremony in the hopes that hunger would help her keep down the raw meat."
-aGot Dany V