After moving to Connecticut, Ward learned that his mistress was pregnant. In late July, he met with her in Washington to discuss how to handle the pregnancy. Soon afterward the woman lost the baby because of complications, the investigation report said.
Investigators said the relationship ended in late July, but Ward stayed in touch with the woman by phone and email to "manage the particulars of the relationship" even after taking command of the submarine.
The documents don't indicate whether the woman knew Ward was married.
"Commander Ward's dishonesty and deception in developing, maintaining, and attempting to end his inappropriate relationship … were egregious and are not consistent with our Navy's expectations of a commissioned officer," wrote Navy Capt. Vernon Parks, commander of a submarine development squadron.
Cragg said the investigation began when a relative of Ward's mistress contacted the Naval Criminal Investigative Service.
Craig reported that Ward was found guilty of Uniform Code of Military Justice violations on Sept. 5, including dereliction of duty, unbecoming conduct and adultery, and received the punitive letter of reprimand.
U.S. Rep. Joe Courtney, a Democrat whose eastern Connecticut district includes the submarine base, said it is a sad situation.
"The Navy doesn't kid around with its leadership," he said. "These positions, to command submarines, are very competitive and I think the Navy is right to hold people to the highest standard."