Draco had a contradictory attitude towards children. They never irritated him, the man was happy to babysit his goddaughter while you and Pansy went out. But to have his own... He was long past seventeen to say 'I'm not ready'. Malfoy knew that he would give the child everything, or at least try. But this does not cancel the fact that he could make a mistake.
He had a pretty good example. His parents were not as bad as many people think. His father carried his wife in his arms, his early childhood was probably the happiest of all possible. Although Lucius, starting from Draco's adolescence, was a little more detached and strict, due to what was happening in the world. Boy always knew that he was loved. Even when his house was teeming with Death Eaters, the only thing he cared about was his family, and his worries about your only nascent relationship.
And it was this experience that gave him doubts. Draco spent years clearing his name of bad fame, learning to live again without the privileges and climbing the career ladder, proving to absolutely everyone that he deserved what he had. And you helped him. But he couldn't imagine that any of this would spill over onto his child. But sometimes he thought about it. About becoming a full-fledged family, so that a little copy of you named after some star would run around the house. It was one of the few traditions of the Black family that Draco liked. And for this it would be worth the risk.
'Sometimes' changed to 24/7 after your conversation, when you brought up the topic of 'what if'. You were clearly nervous, like a small scared kitten trying to check the territory where it steps with its paw. You had never talked about this before. Draco didn't even know why, probably the conversation just didn't come up. And maybe he was a little worried about your opinion to start himself. However, after that that he realized that you were not against it at all. But, he didn't understand completely. How was Malfoy supposed to guess that the his wife was afraid to tell him?