Comic Book Talk

This will be a weird one
I gave a snatch of a memory from a long ago comic
I think it was avengers based but not sure
Essentially a female character meets a guy and they sleep together and she gets pregnant
The pregnancy/birth go very quickly and the resulting baby grows very rapidly and is a full grown man in a week or so (and I’m pretty sure he grows into the man who impregnated the woman)

does this sound familiar at all?
Any ideas or guesses?