Deontay Wilder Details How Daughter Was Conceived ... Extreme TMI!!!

Deontay Wilder has the internet stunned as he detailed how his daughter was conceived ... 'cause the boxing superstar omitted zero details in the extremely graphic story.

The 44-4 heavyweight boxer -- who is scheduled to fight Derek Chisora on April 4th -- was asked about his seven children on Piers Morgan Uncensored on Wednesday ... including his daughter, Naeiya, who has a neural tube defect called spina bifida.

Wilder said Naeiya has made a major impact on his life, especially because of the circumstances.

"Her mother tried to set me up to have the baby," Wilder said. "She injected my sperm in her, ran in the bathroom, locked the door, and that's how we had her."

"Truth be told, she don't even know I know this."

Wilder, 40, went on to explain how he figured it out ... and you can hear the TMI on your own terms in the video.

He then claimed that while pregnant, the woman wasn't taking care of herself -- clubbing, drinking, and not taking prenatal vitamins -- something he believes contributed to their daughter's condition.

"We had the opportunity to terminate the pregnancy, but it's just something in my heart ... I just felt like she deserved to live," Wilder said.

"I wanted to take this opportunity to taking care of a girl born with spina bifida. A child that's in need. She needed me as I needed her."

Wilder went on to call out the mothers of his children ... claiming even though he avoids criticizing them publicly, he still labels them as deadbeat moms.

Despite that, he insisted that he's a devoted father and believes children are more likely to succeed when a father is present at home.

"I always promote fathers take care of your children," Wilder said, "No matter what!"