Mother in Law in Delivery room

Haley • Mommy to Cayde Noah 💙👶🏽 21, Had my little boy on November 19th, 2016. Married to a US Marine 🇺🇸
My husband and his mom are demanding she be in the delivery room. (He's military and will be deployed so he thinks he can dictate who replaces him) Neither of them are understanding that it makes ME uncomfortable and the doctors and nurses will do whatever I'm most comfortable with even if it means she needs to get escorted out. I tried to reason and meet in the middle with she could be the first to see us AFTER delivery, but that isn't good enough. I'm so tired of trying to politely tell her she will not be allowed in the room that I'm almost to the point she's going to get told she isn't welcome to come at all. 
Any advice?!