Oh, that. Thing is, that was said by the military government officials. The officials wanted Historia to become a titan and eat Zeke, but she unexpectedly got pregnant so that plan got scrapped. There's alot of things suspicious about that subject. For one, they mentioned that Historia didn't marry the guy. Secondly, this happened conveniently when the government was about to enact their plan. Third, there was a hooded figure spotted when that happened.
Someone planned all of this. Lastly, there is still no Historia POV. Something must have happened that the author is keeping secret for now. Especially since one of Eren's memory shard had a crying adult Historia. Something happened between them during the timeskip and one of the theories is that Eren is the actual father and planned all of this. /spoiler]