Trystan Reese and his partner, Biff Chaplow, were already seasoned parents when they decided last year that they wanted another child.

Years earlier, they had adopted Chaplow’s niece and nephew after his sister was no longer able to take care of them. They raised the two children as their own, bringing them up in Los Angeles, where Reese and Chaplow worked in nonprofits, then moving the family to Portland, Ore., where they live now.

Adoption was a taxing process, Reese said, and learning how to care for two toddlers ushered in a suite of new challenges and lifestyle changes, as it does for any parent. But it was also eye-opening.

“After the dust settled, I just realized how much I loved our kids,” Reese told The Washington Post, “and how much room there was in our life for our family to grow.”

After trying for several months, Reese, a transgender man, got pregnant. And just weeks ago, he gave birth to a healthy baby boy.

Reese and Chaplow documented the pregnancy in blog posts and on social media, hoping to demystify what it means for a transgender man to give birth and to create a new sense of normalcy for people in similar situations.

Their family’s story — and their willingness to go public with it — reflects a shift in public attitudes about pregnancy and parenting in transgender men as social stigmas have started to chip away and advocacy groups have campaigned for greater acceptance.

Reese and Chaplow, perhaps more than anything else, want to make one thing clear: They are not the first. Far from it.

“People get the idea that this was some experiment that we embarked on,” Reese said, adding that he watched friends go through the same process after transitioning. “This is tested ground. This is something that has been done in a very safe and healthy way. We’re loath to be put in that pioneer category.”

A number of transgender men have gone through successful pregnancies in recent years — and throughout history, for that matter — some of them long after beginning hormone replacement therapy. In one well-known example, the Village Voice published a narrative about Matt Rice, a transgender man who conceived in 1999 through artificial insemination and gave birth to a baby boy. Other more recent pregnancies among transgender men have been well documented in media reports.

Reese, 34, was assigned female sex at birth and lived as a woman until his late teens. After counseling, he began taking hormones around age 20 and started identifying as a man. He met Chaplow nearly eight years ago and said it was “love at first sight.” They took custody of Chaplow’s sister’s children in 2011.

When they decided to have a biological child, they sought out medical advice. Doctors told them that because Reese had only undergone hormone therapy in his transition, preparing to conceive wouldn’t be very different than for a woman who had been on hormonal birth control.

Reese said he became pregnant about five months after he stopped taking testosterone.

“When I found out, it was equal parts elation and fear,” he said. “I was so excited to be on this journey with the person that I love, and then also really scared. Could I do this? Pregnancy is hard, labor is hard, and I hoped that I’d be able to handle it all.”

When Reese was six months along, he addressed people’s curiosities and misconceptions about his pregnancy in a video he shared on social media. Sitting on his couch with a melon-sized bump under his shirt, he explained how the testosterone he took caused him to grow facial hair and made his voice drop but left him with a functioning uterus and ovaries.

“I’ve never wished or wanted to be assigned male at birth or to have my body match up exactly with that of my partner, who was assigned male at birth,” Reese said. “I’m okay being trans. I think it’s kind of awesome, actually, and I’ve never wanted my body to be different.”

“If you can understand that then it starts to make more sense that it would not seem totally bizarre for me to want to create and carry a baby, because I don’t wish that my body was not a trans body,” he said. “I’m okay being a man who has a uterus and who has the capacity and capability of carrying a baby.”

Reese’s pregnancy had all the ups and downs of any pregnancy, complete with swollen feet, fatigue, mood swings and all the anticipation and excitement that comes with bringing a child into the world, he said.

On July 14, after 30 hours of labor, Reese gave birth to Leo, a 9.5-pound baby who he says is in great health.

Reese told The Post he never imagined his life would take such a turn when he began his gender transition some 14 years ago.

“I didn’t think I would ever find someone I would fall in love with and would be with me. Being able to adopt two brilliant, funny, sweet kids was something that I never dreamed of. The fact that any of this happened has been a total surprise to me, because that’s not the trans story we’re told, that love is possible, that being a loving family is possible.”

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