The Uterus Monologues

From time to time I get asked to simplify scientific facts for the children’s books I write, so they are more easily understood by our six to nine-year-old readers.
Usually it’s no big deal, but I was given this fact the other day and it’s proving to be quite a challenge:
“Embryonic great white sharks do not have a placenta and obtain their nourishment by feeding on eggs in the mother’s uterus.”
I am quick to isolate the three problem words: embryonic, placenta, and uterus. “Embryonic” can be changed to “baby great white sharks before they are born.” “Placenta” is only mentioned as something they don’t have, so I pretend it’s not even there. That leaves “uterus.” If I try to ignore that, too, my simplified fact reads “Baby great white sharks before they are born eat their mother’s eggs.” This makes “fried or scrambled?” seems like a logical follow-up question. Clearly, I need to introduce the uterus, but how? I can’t call it a tummy, because not only would that be physiologically incorrect, these kids know their tummies are what makes them throw up when they eat an entire box of Fruit Roll-Ups in one sitting. “Womb?” Biblical overtones. “Belly” is non-specific. And “privates” makes sharks sound like prudes.
My plan is to give the uterus a cute nickname, like Oprah’s trademark va-jay-jay. Right now I’m leaning towards utee-patootie, but any suggestions are welcome.