INDIANAPOLIS (AP) — A retired Indianapolis fertility doctor who lied about using his own sperm to impregnate as many as dozens of women has surrendered his medical license.

An attorney for Dr. Donald Cline surrendered his license Thursday during a hearing before the Indiana Medical Licensing Board. The board then voted to bar Cline from ever seeking reinstatement of his license.

Cline was given a one-year suspended sentence in December after pleading guilty to two counts of obstruction of justice. He’d used his own sperm to impregnate as many as dozens of women after telling them the donors were anonymous.

Indiana law doesn’t specifically prohibit fertility doctors from using their own sperm.

Children of women Cline treated say DNA tests show he’s likely the biological father of as many as 20 of them.