The couple say they have not had full sex change

A transgender couple raising two sons are preparing for the day they will have to sit their children down and tell them that it was their father who gave birth to them.

That's not all either, as that same day the boys will also learn that it was their mother who got their father pregnant.

This is because Bianca and Nick Bowser never had their sex organs removed, and used them to have children of their own.

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Nick Bowser is a transgender man who gave birth to his two sons, Kai and Pax (above)

Nick has been married to Bianca (right), a transgender woman, since 2011

Bianca, 32, was born as a boy called Jason, while her husband, Nick, 27, was once a girl named Nicole.

The couple from Kentucky, who married in 2011, say they have no intentions of hiding their pasts from their sons, Kai, three, and Pax, one.

'I mean, that’s when we tell them sometimes men have babies, and sometimes mommies can’t have babies,' Nick told ABC News.

'We’re telling them the truth, and I think that’s the most important thing, and in a way that they can understand.'

Bianca previously explained to Holly Willoughby and Phillip Schofield on This Morning: 'It's always something that I have looked forward to, telling our children.

'It's nothing we are ashamed of so I have no dread telling our children where we came from or how we previously lived our lives.'

Nick added: 'We will tell them when they are ready, when they start asking questions about me being pregnant and about the old family pictures they may see of me dressed as a girl and Bianca as a boy.

'As they get older they will understand more. We feel being honest with them from an early age will preserve the relationship we currently have with them.'

The couple say they will be open with Kai and Pax when the time comes and speak about their past

'I mean, that’s when we tell them sometimes men have babies, and sometimes mommies can’t have babies,' said Nick

The pair both grew up feeling different and eventually realised it was because they were living as the wrong gender.

Bianca said: 'At five, there was a moment when I was playing with other classmates that I felt different. I didn't fit in with other boys. I didn't like sports or masculine games. I had a really hard time growing up.'

She transitioned to live as a woman more than a decade ago, having breast augmentation in 2003, as well as laser hair-removal. But she has not yet had reconstructive surgery and so was able to father their two sons.

Meanwhile, Nick started living as a man after he turned 20. He also had a difficult time growing up as he felt conflicted over who he was.

He explained: 'I first came out as a lesbian at 17 and I thought that solved my problems. As a child I wanted to dress as a boy and do boys things but I wasn't able to. I thought all lesbians thought the same as I did.

'It wasn't until I was 20 that I discovered I could change my sex and be comfortable with who I was. I met transgender people and I finally figured out what would make me happy, which was not being a lesbian but being a guy.'

As he is also yet to have surgery to fully complete the sex change, Nick was able to become pregnant with their sons after he met Bianca in 2009 and they decided to start a family.

While he said the process was completely worth it, he also admits it was a difficult time when his body and mind were in constant conflict.

'Being pregnant was extremely difficult for me,' he said. 'I don't regret the decision to carry the children but at the same time, my brain and body were fighting.

'My body had turned into the ultimate version of female and my brain was telling me, "you're not female, you're male". When I looked in the mirror, it was a constant battle for the nine months I was pregnant each time.'

'We’re telling them the truth, and I think that’s the most important thing,' says the couple

Both Bianca and Nick intend to have surgery in the future and it is currently only the cost that is holding them back.

In the U.S, male to female surgery can range from £4,000 to £15,000, while female to male surgery can exceed £30,000.

Nick said at the moment, they can't afford such an expense as they would rather spend what money have have on their sons.

He said: 'When it comes to surgery in the U.S, most of the time you have to pay out of pocket. As we both need surgery, it's a lot of money and we have two children.'

The couple have been happy to share their story with world media in the hope of banishing prejudices towards transgender people.

Nick said: 'We do everything any other parent would do. We went through the same process and preparations except I was at the one who carried the two children.'

However, he said not everyone has been fully supportive of their choices, especially in their home country.

'The U.S. is behind with equality for people like us,' Nick said. 'We still have a large amount of people who are against who we are and the two of us having children together. We have received some pretty hateful comments from people in the U.S.'