A question about the orc camp bad end?

[leomax]

The bad end where arona gets mad everyone else is pregnant what triggers that besides just having them all pregnant, is it random?

 

[Tarnakus]

If you mean the orc breeder end then:
Things I'm sure about:

• Arona can't be pregnant at all - even if she didn't told you she might be already pregnant,
• Ragnild, Hretha and Infrith must be pregnant and in late stage of pregnancy.

I'm not sure if needed:

• I did Arona fertility quest,
• I have all bodyguards pregnant (also in late stage, I have all orcs from camp impregnated on the same day).

No it's not random and it triggers on entry tile of orc camp. You don't need Arona in party to trigger it.