Robert Kawada is charged with poisoning, assault and battery with a dangerous weapon on a pregnant person, and assault and battery on a household or family member, the Middlesex District Attorney said.
Watertown police believe Kawada gave the woman Misoprostol, a drug commonly used to end pregnancies. Planned Parenthood said the medication is 85 to 95 percent effective up to 11 weeks from conception.
Investigators didn't provide any information on when the alleged drugging happened only that Kawada told the woman he was giving her iron pills and vitamins.
He will be arraigned on charges on Tuesday, May 28.
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