I just tried that and realized that it is not only a WoW issue, but if I have mc command center at the same time then it becomes an issue. With both of the two mods individually it is fine. Are the two no longer compatible?
I made a brand new save with just those two mods installed and the problem is still there. I had brand new versions of both of the mods so none of the settings had been changed at all. I began playing around with the settings but nothing seemed to impact it.
Tested it with both the setting on and off, still can't seem to be able to recreate it.
If you turn that setting off though WoW stops having anything to do with pregnancy, and it's all controlled by MCCC or any other mod you might have installed.