Skim a list of syndicated comic strips, and you'll see that men write the great majority. Thus, it isn't surprising that women appear less often in the comics themselves.
Daniel Fernandez-Baca, a graduate student in sociology at the University of Florida, studied the top syndicated comics in 2008 that still published new strips: “Blondie,” “Beetle Bailey,” “Family Circus,” “Hagar,” “Garfield” and “Dilbert.” They appeared in at least 1,500 newspapers, magazines and other media. That fact alone should make you weep. A news release quoted him:
"When they do appear, for the most part, women don’t say anything funny or act humorously, but merely set up the joke and allow men to create the humor." ... While single women are portrayed as desperate to marry, once married they are often depicted as nagging housewives who berate their husbands, he said.My thanks to the Comics Section blog, which helped me narrow the search for sexist comics before blood spurted from my eyes.
ETA: Cathy Guisewite has announced that she will retire "Cathy," the first comic strip by a woman to be syndicated nationally.