Caveman Alien's Ransom by Calista Skye.
Being abducted by aliens was never on my bucket list!
But I guess the aliens didn't get that memo, because one night I was beamed aboard a UFO. It dumped me and a bunch of other girls on an alien planet!
A jurassic planet where giant, murderous dinosaurs walk around and everything wants to kill me. My only hope of surviving is the first man I met here. His name is Jax'zan, and he's an alien...
And a caveman!
As in, the hottest super-alpha caveman who ever lived. He's big and strong and doesn't talk much, but he's saved my life so many times now that I've lost count. My insides turn to hot mush whenever he fixes his smouldering eyes on me, and the scandalously sexy and unusual features his sensationally muscular body is rocking totally make me forget time and place. There's only one problem: He's holding me for ransom. And he wants to repopulate his woman-less planet. With me...
The plants that grow babies are called Lifegivers:
Then we go to check out the Lifegivers. Sophia described them to me, and these look a lot like those.
They're basically plants, but they also have some animal in them, and probably some fungus stuff, too. They move and look weird, and they can provide a human fetus with everything it needs to grow to birth size.
Ar'ox peels away the layers of green and red leaves until I can see a translucent pod with what is clearly a human fetus inside, suspended in a cloudy liquid.
The mountain does indeed turn out to be a spaceship:
“Sophia,” she says, and her voice has a strange tremble to it. “If you look at the top of that mountain ... and you squint a little ... doesn't that look like something else?”
The sun is low behind the trees and I shield my eyes with one hand. From this angle, a part of the mountain near the top is rounded and strangely symmetric. Unnaturally so. And it has a sharp edge that seems perfectly circular. There's green vegetation all over it, so I can't see any specific details. But the color is different than the rest of the mountain below, lighter and somehow more even.
My hand flies unbidden to my mouth. I've seen my share of sci-fi movies and then some. I recognize a rocket engine nozzle when I see one. And I'm looking at one right now.
Found by Googling for women abducted dinosaur science fiction site:goodreads.com/book/. It was third in the list.