Radio seemed to be more open to female hosts than tv. Arlene Francis might have that title, as far as national goes. Maxene Fabe's book lists 1938's What's My Name? as being hosted by Wilbur Hulick and Arlene Francis. Not clear if they were co-hosts, or Arlene later superseded Hulick. Blind Date with Arlene started in 1943, as did Irene Beasley's music quiz Grand Slam. Arlene hosted the tv version which is listed as starting in 1949, so I'd lean her way. Kathy Godfrey (Arthur's sister) co-hosted a version of On Your Way with John Reed King in the early 50s.