Check out this OP from a forum about Skyrim:
Ok so it's been heatedly debated, argued, angrily shouted and flamed over breast cups on female plate armor breast plates.
It's now so much that the mod comments pages get flooded and some locked over this.
In an attempt to bring this debate to an end I contacted Professor Clifford J. Rogers. he's a professor of history at the United States Military Academy at West Point. He has also been a Leverhulme Visiting Professor at Swansea University, an Olin Fellow in Military and Strategic History at Yale, and a Fulbright Fellow at the Institute of Historical Research in London. If anyone HE would be the one to end this debate once and for all.
I Contacted prof. Rogers over facebook and asked him about this and here is my question and his answer.
"Did the few women in medieval history that actually wore armor have breast cups on the breast plate or wear male armor with the breast tied down? Also wouldn't breast cups on the armor be counter-effective vs blows, arrows etc in the way that the impact wouldn't be deflected away but actually caught and helped find the center chest and thus assist the enemy in killing the wearer of said armor?
lastly, can I quote your answer on skyrimnexus.com?
and his answer:
"Per, The number of women who wore plate armor in the Middle Ages is extremely, extremely small. I can think of only 2 probable examples, Joan of Arc and Big Margot (and the latter may not have been wearing plate). More common-- mainly because it was in use much longer-- would be mail armor. However, I think fantasy-style breast cups would be very unlikely; as you say, they would not serve well for deflection, which is very important. Also, the fifteenth-century illumniations of Joan show her in essentially male armor, not with breast cups. There's also a 15th c illumination of Minerva in plate armor in British Library MS Harley 4431 fo. 102v, which you could view via the British Library ImagesOline site. And see Bibliotheque nationale de France, MS FR226 fo. 58 for another woman in basically a male breastplate.
Yes, you may quote me.
So there you have it people. Though it might look sexier that way, the only person that wore armored breast cups was probably Red Sonja