A Michigan mother is facing a trial after being accused of having a summer romance with the teenage son she gave up for adoption.

Aimee Louise Sword, 35, who is free on bond after her arrest, was initially charged with three counts of felony third-degree criminal sexual conduct. A judge this week reduced the charges to one count, but police say she is accused of a "very serious crime."

Sword began a sexual relationship with her biological son in the summer of 2008 after reconnecting with him on the Internet, Waterford Township Police Sgt. Scott Good told ABCNews.com.

"She had given the child up early on in life for adoption," he said, adding that Sword's adoption agreement permitted limited contact with the boy.