A Garrison woman accused of causing the death of her unborn child by overdosing on drugs has pleaded not guilty to six felony charges and one misdemeanor, said McLean County State's Attorney Ladd Erickson Wednesday.

Michelle Geiser entered the pleas to South Central District Judge Sonna Anderson Wednesday at the McLean County Courthouse.

Erickson said Sam Lincoln of the Mercer McLean County Drug Task Force has came up with an additional 13 last names that Geiser has gone by including the names Behles, Kaltenberg and Weeks.

Geiser, 34, was charged in October with Class A felony endangerment of a child, Class C felony possession of a controlled substance and four Class C felony counts of acquiring a controlled substance by deception. Geiser also faces a Class A misdemeanor charge of ingestion of a controlled substance.

According to an affidavit from Lincoln, also a McLean County Sheriff's deputy, the Garrison Ambulance Service was called to a Garrison home on Sept. 24 for a report of an unresponsive female. Ambulance personnel found pill bottles near Geiser, who was semi-conscious. The bottles were for hydrocodene, locet and cyclobenazeprine, the affidavit said.

Geiser is accused of possessing and ingesting those drugs, as well as tizanidine, without valid prescriptions.

An ultrasound performed at Medcenter One showed the baby she was carrying had no heartbeat. Documents said a doctor at Medcenter One found that Behles had toxic levels of several drugs in her system, and the baby, which was more than 29 weeks along, did not survive the overdose.

Dr. William Massello, the state forensic examiner, performed an autopsy on the child and found that "the child would have been viable outside the mother's womb, however the baby would have needed assistance."

Behles also has been accused of using the fake name "Ashley Benderson" to acquire hydrocodone and cyclobenzaprine at a Washburn drugstore; the name "Melissa Anderson" to acquire hydrocodone and zanaflex from a Turtle Lake drugstore; the name "Allison Hendrickson" to acquire hydrocodone and soma from a Turtle Lake drugstore; and the name "Michelle Bahles" to acquire hydrocodone from a Turtle Lake drugstore.

According to another affidavit from Lincoln, Behles was identified through photograph lineups by employees of the drugstores as the person who used the names when purchasing the drugs. The affidavit said Behles is alleged to also have used fake Social Security numbers, dates of birth and mailing addresses in three of the incidents.

The case was investigated by the Mercer-McLean County Narcotics Task Force, of which Lincoln is a case agent.

According to the affidavit, Geiser has a criminal history related to illegal possession and acquisition of prescription drugs. It said she has served time in a Minnesota women's prison for attempting to obtain a prescription in Polk County, Minn. She also has convictions for possession of Valium, obtaining a controlled substance by fraud, and multiple convictions for issuing checks without sufficient funds.

Geiser has been released from jail on a $10,000 bond, which was posted by her father, Ronald Geiser.

Her next court appearance is slated for Dec. 19.

(Reach reporter Jenny Michael at 250-8225 or jenny.michael@bismarcktribune.com.)