Woman claims former OB-GYN artificially inseminated her, 9 other women with his own sperm

WHITEFISH BAY, Wis. (WDJT) - A Wisconsin woman claims her former OB-GYN artificially inseminated her and nine other women with his own sperm without consent.

Joseph Laedtke-Heider was born in 1983 after his mother, Mary Ellen Lukezich, sought fertility treatment with her husband. Lukezich says Dr. Frederick Dettmann, her OB-GYN at the time, suggested using the sperm of an anonymous donor.

“The anonymous medical student donor that my mother was promised as my biological father never existed,” Laedtke-Heider said.

Laedtke-Heider reportedly discovered through genealogy testing in December 2024 that he had nine half-siblings and was able to trace it all back to Dettmann.

“Words cannot fully express what it feels like to learn that your entire identity is built on a lie,” Laedtke-Heider said.

The family is looking to file a civil suit in the next 60 days, alleging battery.

“Dr. Dettmann committed the ultimate betrayal, a doctor who was supposed to be caring for his patient instead secretly impregnated his patient with his own sperm, without her knowledge, without her consent and against her understanding of her care,” attorney Al Foeckler said.

Dettmann, now in his 90s, worked for decades at his Whitefish Bay office. This isn’t the first accusation against him.

Whitefish Bay police logs indicate a woman accused Dettmann of sexually assaulting her during an exam in 1985, an allegation he denied. The assistant district attorney reportedly declined to issue charges as “burden of proof was too difficult,” and in 1986, the medical examining board closed the case.

Police say there are no current investigations into Dettmann.

The following statement was released on the doctor’s behalf:

Dr. Frederick Dettmann, a board-certified OB/GYN, spent his medical career focused on surgical specialties: cancer surgery, high-risk surgery, reconstructive and reproductive surgery, pioneering many medical advancements still utilized in modern medicine. He held numerous leadership positions within the medical profession and was recognized both in Wisconsin and nationally for his contributions to medicine and patient care. After a distinguished career, Dr. Frederick Dettmann retired from active practice in the early 1990s. Throughout his esteemed career, Dr. Dettmann was never sued, disciplined, investigated, had his licensure challenged nor were any ethical complaints ever made against him.

Dr. Dettmann, currently age 91, is aware of the claims being suggested. Due to HIPAA and Wisconsin’s medical confidentiality laws, he cannot comment on any patient care he rendered during his career. The events referenced are alleged to have occurred almost 50 years ago. Dr. Dettmann has no independent recollection of the individuals making these allegations and is unaware of any evidence supporting the claims being asserted.