I had 38cm bars initially on my road bike, they seemed alright in the shop but in practice were too narrow and my boobs also got in the way. I found the bike teetery when I stood up to climb and just got fed up with squashing my boobs. I persevered with it for a year as I am a mountain biker and my MTB handlebars are 26inches wide, they were always going to feel narrow, but I had to change them in the end.

I have changed them to 42cm Deda 215 Shallows (I think, definitely 215 shallows, manufacturer escapes me) and the difference is amazing. I have real leverage when standing pedalling and my boobs don't get squashed, much more enjoyable riding experience.