Health-care conglomerate Johnson & Johnson lost its motion to reverse a $4.7 billion jury verdict awarded to women who blamed ovarian cancer on asbestos in the company's baby powder and other talc products, a Missouri court ruled Wednesday.

In his ruling, Missouri Circuit Court Judge Rex Burlison said there was "substantial evidence" of "particularly reprehensible conduct" by J&J, saying that executives "knew of the presence of asbestos in products that they knowingly targeted for sale to mothers and babies, knew of the damage their products caused, and misrepresented the safety of these products for decades."

Shares of the company slipped 1 percent to $129 a share in afternoon trading. The stock is now down almost 13 percent so far this month, putting it on pace for its worst month since February 2009.

The company in a statement said the motion before Burlison was just a formal step before J&J could file an appeal with the Missouri appeals court.

"The same judge has denied similar motions on prior verdicts in his court that were ultimately overturned by the appellate courts. We are confident this verdict will also be overturned on appeal," J&J said in a statement.

Lawyers for the women did not immediately respond to requests for comment from Reuters.

The women and their families said decades-long use of baby powder and other cosmetic talc products caused their illness. They allege that the company knew its talc was contaminated with asbestos since at least the 1970s but failed to warn consumers about the risks. A jury in July awarded $550 million in compensatory damages and $4.14 billion in punitive damages.

Reuters reported on Friday that J&J knew for decades that asbestos, a carcinogen, was in its Baby Powder.

On Tuesday, the plaintiffs' attorney Mark Lanier said on CNBC's "Squawk Box" that the plunge in the company's stock helps his case. The $4.7 billion verdict he won for his clients is just a fraction of the more than $50 billion in market value that J&J has lost since scathing articles were published by Reuters on Friday and The New York Times over the weekend.

"It serves my purpose as a litigator to say, 'Yes, get their attention, keep driving the stock down,'" he said.

The company denies that its talc products cause cancer or that they ever contained asbestos. It says decades of studies show its talc to be safe and has successfully overturned previous talc verdicts on technical legal grounds.

The majority of the thousands of lawsuits that J&J faces involve claims that talc itself caused ovarian cancer, but a smaller number of cases allege that contaminated talc caused mesothelioma, a tissue cancer closely linked to asbestos exposure. The cases that went to trial in St. Louis effectively combine those claims by for the first time alleging asbestos-contaminated talc caused ovarian cancer.

Reuters contributed to this article.