Gorilla's share a remarkable amount of their organs and genetics with humans, so baby gorillas develop in the womb in a very similar way to baby humans. Food and oxygen are passed down the umbilical cord and through this the foetus strengthens and grows.
The life stages are also extremely similar to humans, starting as an egg, then zygote, then embryo then foetus. They take roughly 8.5 months, give or take, to develop fully. This is only just short of the 9 month term humans exercise.
Gorillas were originally thought to be monkeys, but it is now understood that they belong to the ape family. Humans share approximately 98% of their genes with apes, so it is easy to see how similar a baby gorilla's development in the womb would be to ours.
I hope this helps.
