SAN RAFAEL, Calif. - A fertility specialist doctor who implanted the wrong embryo in a woman and allegedly engaged in an 18-month cover-up has lost his medical license and must close his practice on Wednesday.

The Medical Board of California ruled last month that Dr. Steven Katz no longer allowed to practice medicine because they do not tell the truth to the two women involved in the confusion.

Katz, who has offices in Greenbrae in Marin County and San Francisco, requested the Board to reconsider its decision, but the junta refused to do so April 20.

“This case concerns some of the most serious mistakes that the doctor can imagine, and nothing less than the repeal will be to restore public confidence that this type of behavior will not be tolerated by the medical profession,” wrote Administrative Law Judge Jonathan Lew.

His recommendation, contained in a 23-page proposed decision to revoke doctor’s license was approved March 28 by the medical board.

The confusion occurred in June 2000, when Katz implanted three embryos for another woman in Buchweitz Susan Campbell. The embryos were created by in vitro fertilization with sperm from the husband of the woman, and the eggs from donors.

Katz, who runs Fertility Associates of the Bay Area, he realized the mistake within 10 minutes of the proceedings after his embryologist, Imam El-Danasouri, saidthe doctor had given wrong embryos, according to the decision .

“The defendant was surprised. He stated that his reaction was such that I almost fainted,” the decision said.

Katz refused to respond, but his lawyer, Robert Sullivan, of Sacramento, said: “The penalty is excessive and is purely punitive.”

Sullivan said Katz plans to appeal the decision of the Board in Sacramento Superior Court.

“That was years ago. This is a unique set of facts. Yes, the doctor made a mistake,” Sullivan said, but added that Katz had learned from experience and improve its procedures.

Sullivan also said the purpose of removing the license of a physician is to protect the population and to rehabilitate the physician, not to restore public confidence, as stated in the decision.

Sullivan argues that one of the experts of the medical board, Dr. Eldon Schriock, operates a fertility clinic in San Francisco and is a competitor of Katz.