Disclaimer: "LOST" is the property of ABC.
This is exactly why they never tried to have a baby.
Cole wanted to. Eventually. She said if Ben trusted Juliet so much then she must be close to fixing the problem. Danny said Ben trusted Juliet so much because there wasn't any other choice. That was the only time they ever fought about it.
Danny wanted kids too. It wasn't like he was against the idea. It was just that he didn't see any change in how long the pregnant women were surviving. And yeah, of course he knew that it would never becompletely safe, but right now no one had managed to actually live long enough to give birth. So he didn't care that if would be nice to have a baby, because right now that would mean losing Cole, and he couldn't bear that.
But as it turned out, having a baby wasn't what was going to take Cole from him. It was them. He should have known. Goddammit. He should have known that a jumbo jet crashing on the island could only be a bad thing. Ben might go on about good people and what the island wanted, but Cole was a good person, wasn't she? Hadn't she been handpicked by Ben? Brought to the island by Richard? So why would the island let one of them kill her?
Danny didn't even hear what Tom was saying to him. He had to get out -- out of this room, where all he could see was his Cole lying so still, white in the harsh light and against the red of her blood, splattered everywhere. He had to get out, find one of them, see their blood against the white of their skin, against his own skin.
Cole had wanted a baby and he'd been too scared to make her happy, too scared that her happiness would cost him his. Now he'd lost that chance to make her happy. Because of them. He was going to make sure that he took their happiness away, too.