Hm, this second article seems to not consider the possibility that pregnancy is when the abuser knows he has you trapped.

Perfectly nice and normal men do not suddenly turn into murderers because of stress. And I am very sceptical about the claim that any kind of domestic violence is caused by stress, unless you call "yelling at someone for no good reason" violence. (Have you read "Why Does He Do That?"? It's a book by a guy who worked with domestic abusers, and he has some very interesting insights about the whole "he's just angry" thing.)