I just noticed that #AWS #reinvent has lactation rooms at Caesars, Venetian, MGM, Encore, Wynn, Mandalay Bay, Monday through Thursday, 6:30 am to 9 pm (Thursday until 8); Caesars and Venetian on Friday from 7 am to noon.
Please alert any new moms attending who might not know about this; beats having to try to get back to your hotel room.