For years, one of the main criticisms of beer advertising was that it tended to either objectify women or disregard them entirely. Marketers seemed to be too busy trying to appeal to the young male audience they knew would consistently drink beer by the case to worry about anyone else.

Now, that appears to be changing.

Allen Adamson, the former chairman of the brand consulting firm Landor Associates, said the fraternity house imagery and sophomoric humor that long defined many beer campaigns has come “under siege,” led by millennials who are more conscientious about male chauvinism.

With more consumers switching to craft beers — which grew to 10.7 percent of the dollar share in 2015, according to Nielsen — and beer’s already having lost 10 percentage points of its volume share to wine and spirits since 2002, the major labels have had to refocus their efforts, Mr. Adamson said.

“It was fine to show a frat party making fun of girls five or eight years ago,” Mr. Adamson said. “But it’s ineffective and potentially damaging to do today.”