Dr Donald Cline. Photo / AP
A retired Indianapolis fertility doctor said he used his own sperm around 50 times instead of the donated sperm his patients were expecting, impregnating several women decades ago, according to court documents.
Dr Donald Cline, 77, pleaded not guilty today to two criminal obstruction of justice charges for misleading authorities who were investigating complaints from two of the now-adult children against him.
Cline is accused of being the biological father of at least eight people, the youngest of which would be about 30.
The accusations against him were first reported by WXIN-TV in May.
The 77-year-old from the Indianapolis suburb of Zionsville told six adults who believed they were his children that he had donated his own sperm about 50 times starting in the 1970s, a probable cause affidavit said.

One of the adult children took a saliva-based DNA test through a private personal genomics company and found that she was related to at least eight other people in its database, the affidavit said.He had told his patients they were receiving sperm from medical or dental residents or medical students and that no single donor's sperm was used more than three times.
Two others also investigated their ancestry through DNA tests and learned their mothers both were patients of Cline and that they were related to 70 relatives of Cline, it said.
Cline "said he used his own sperm whenever he didn't have a donor sample available," the affidavit said he told them.
But when the state began investigating complaints, Cline denied having done so.
"I can emphatically say that at no time did I ever use my own sample for insemination," he said in a letter to the Indiana Attorney General's Office.
Cline retired from his practice at Reproductive Endocrinology Associates in Indianapolis in 2009.
Cline's lawyer, Tracy Betz, released a statement saying he is not accused of hiding documents, influencing witnesses or otherwise not cooperating with the attorney general's investigation.
The most notorious fertility doctor to secretly use his own sperm was Cecil Jacobson, who may have fathered as many as 70 children from 1976 to 1998 in Vienna, Virginia.
And in 2009, Dr Ben Ramaley of Greenwich, Connecticut, quickly settled a 2005 lawsuit for using his own sperm.