Transgender man switches back to female to generate eggs. Embryo placed in wife's uterus — and son with 'two genetic fathers' is born.

"Arlo has two genetic fathers," Seth Marlow told The New York Post. "He's a pretty unique kid."

Marlow was speaking the paper about son Arlo, now 4 years old — and who was conceived in a rather unorthodox manner.

What are the details?

Seth Marlow, 41, transitioned to male in 2003 and got a double mastectomy, the Post said, adding that Marlow's ovaries remained intact.

After meeting wife Leah, Marlow transitioned back to female in 2012 by stopping testosterone treatments and getting estrogen in order to generate enough eggs so in vitro fertilization could take place, the paper said.

"It took quite a psychological toll on me, but I was determined to see it through," Marlow added to the Post.

More from the paper:

As a result of the estrogen, Seth's body redeveloped curves. After three months, he got a period. In the podcast ... he reveals how he had to sneak tampons into the men's restrooms at a Chicago airport when he unexpectedly began to menstruate while in transit.

'I'm a dude with a big beard and a bunch of tattoos'

"I'm not a big dude, but I'm a dude with a big beard and a bunch of tattoos," Marlow told the Post. "My trans history only is disclosed if I choose to disclose it."

The egg retrieval occurred at a fertility clinic, then the couple chose an anonymous donor to fertilize the eggs, after which they were frozen, the paper said, adding that Marlow immediately switched back to male.

In early 2015, one embryo was transferred to Leah's uterus, the Post said, and 6-pound, 3-ounce Arlo was delivered in October of that year.

“I thought my transition had cost me my fertility and the path to a family," Seth Marlow told podcast “Pregnantish," adding that staying a "confirmed bachelor" seemed inevitable before Leah came along, the paper said.

“I longed for but never thought I would have my own biological child," Marlow also said, according to the Post. "But as soon as Leah and I got serious, and I suggested this course of action, she said: 'I'm in!'"

Despite a dispute with their health insurance company — the Marlows paid around $30,000 out of pocket for the procedure — the paper said they want more children.

'Will we be using your eggs, Daddy?'

“Recently, we were talking about hopefully adding a little brother or sister to our family and Arlo said, 'Will we be using your eggs, Daddy?'" Seth Marlow recounted to the Post. “He doesn't understand the mechanics of the sexual act, but he knows about all the different ways a baby can be created."

Indeed, the paper said, 13 of their embryos remain frozen in the lab, and one will be defrosted and placed in Leah's uterus within the year.

“It's a beautiful way to make a family," Seth Marlow told the Post.