Family alleges OB-GYN used his own sperm for insemination instead of agreed-upon donor’s

U.S. newsFamily alleges OB-GYN used his own sperm for insemination instead of agreed-upon donor’sJoseph Laedtke, 43, learned through an ancestry test that he had nine half-siblings, who he says connect back to his mother’s fertility doctor from the 1980s.Listen to this article with a free account00:0000:00Joe and Mary Ellen Laedtke.Courtesy Laedtke familyShareAdd NBC News to GoogleJune 12, 2026, 6:29 AM EDTBy Doha MadaniWhen Joseph Laedtke got the results of his ancestry DNA test in December 2024, he was shocked to learn he had nine half-siblings. And that they all seemed to trace back to his mother’s former doctor.Subscribe to read this story ad-free Get unlimited access to ad-free articles and exclusive content.Mary Ellen Lukezich and her late husband, Thomas Laedtke, went to see Dr. Frederick Dettmann in the early 1980s when they were struggling to have a child, she said. The Wisconsin couple spent two years undergoing fertility treatments and eventually agreed to undergo artificial insemination using donor sperm.She remembered that Dettmann suggested using donor sperm from a medical student. Lukezich told NBC News that she was assured upon asking questions of Dettmann that the donor was unlikely to donate again, that he was from out of state and that he was chosen to closely match her and her husband’s appearance.“I was young,” Lukezich said. “I so wanted to be a mom that I was going to do anything, and I did whatever he asked me to do.”She and her husband kept the decision to use donor sperm private, she said.“This was our personal road, and no one needed to know. I got pregnant, everyone was happy, and that was the end of the story,” she said. “It was great. I tried again, but I never got pregnant again.”It wasn’t until her now 43-year-old son submitted his DNA to a genetic testing company that she learned her doctor may have used his own sperm to inseminate her.Laedtke said that when he submitted the test around November 2024, he wasn’t expecting the results...