Dr. Jen Gunter, an obstetrician and gynecologist in the San Francisco Bay Area, didn’t mean to pick on Goop, Gwyneth Paltrow’s lifestyle and wellness e-commerce company. In fact, she’s a fan of Ms. Paltrow’s acting.

“‘Shakespeare in Love’ is one of my favorite movies,” Dr. Gunter said. “She was so wonderful in that movie.”

But she doesn’t think much of the stories posted by Goop on health and sex. One that sent the doctor to her blog earlier this year was the suggestion in a Goop story that women insert jade eggs into their vaginas to improve their sex lives.

“I read the post on Goop, and all I can tell you is it is the biggest load of garbage I have read on your site since vaginal steaming,” Dr. Gunter, 51, wrote on her personal blog, which carries the tagline “Wielding the Lasso of Truth.”