"I've only been on testosterone for a year and five months," the 24-year-old, from Ohio in the US, says.
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"I finally felt like myself. I gained so much self-respect, regained my self-confidence, re-ignited my passions and, most importantly, I was actually happy. And it showed." McElroy, born in a female body, describes his childhood self as a tomboy.
I thought I was male
"Since age four, when I started forming memories, until I was about nine, I thought I was male and didn't understand why my brother looked differently than I did."
The term transgender refers to people whose gender identity does not match the conventional cultural expectations associated with the biological sex they are born into. There is, however, no correlation between transgender identity and sexual orientation.
Sexologist, academic and clinical social worker Ronald Addinall says the importance of support to transgender clients cannot be overstated.
The trans community face a number of additional stressors, including negotiating their gender identity with their families, communities and society.
"Thus it is essential that support services exist and are accessible at the personal level, the familial level, the community level, in education and work spaces, as well as access to good quality medical care." McElroy recalls the time before he began his transition. "I was just angry all the time pre-T. No one ever really understood why. Not even me.
"I just had this deep-seated anger that would rear its ugly head, quite often over meaningless things. I was never violent, nor did I self-harm, but it seemed I was just a very short-fused time bomb waiting to explode." He felt particularly uncomfortable about wearing traditionally feminine clothing, which "made me vulnerable, anxious, and exposed", and from teenage years adopted a more masculine wardrobe.
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When he reached the decision to begin the process of transitioning, McElroy felt somewhat daunted at the prospect of having to "come out to my parents a second time - the first time, telling them I was a lesbian," at age 16.
In the event, McElroy's close family were extremely supportive.
"The first thing my dad said to me was: 'Well, you're going to need a better hair cut'. My mom said: 'So what's your name going to be?'" After some discussion McElroy, who was previously known as Meghan, and his mother settled on the name Niko.
He says he was "absolutely ecstatic" at beginning the hormone replacement therapy (HRT) injections that would help bring his physical appearance in line with his gender identity.
"Initially [I was] a bit nervous due to the need for self-administered intramuscular injections... every 10 days for the rest of your life.
Seamless physical transition
"Once I had gotten used to administering my medicine and started seeing and feeling changes, I knew that this was the best route and the only one for me to take." McElroy enjoyed an "extremely seamless" physical transition.
"At about 30 days I started to notice a significant change in my facial structure. This is unusually fast." In his mid-teenage years, prior to his HRT, McElroy and his family moved to a larger town.
"I have seen a few people that I grew up with since and they either didn't recognise me, or were unfazed.
"Some of my closer friends and relatives said that it's because it seems so much more natural; it fits." In common with a number of trans people, McElroy refers to his former self in the third person.
"But only because I feel completely different in every way, shape, and form... I'm pretty open to my past. I don't hide from anything. I embrace it." Asked if he has any regrets, he says: "None. I only wish I had figured this out sooner".
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"I don't really remember how I started questioning my gender identity, but I do know that I began watching YouTube blogs from other transmen and listened to their explanations about how they felt prior to transition and related to most of what they said." McElroy feels that reaching this realisation was even more important than the physical transition itself.
He and a friend subsequently started a YouTube channel, NikoandKage, to document their own experiences with testosterone and masculine lifestyle.
However, McElroy was somewhat enigmatic when asked to provide an insight into what masculinity physically feels like.
"Masculinity feels like the opposite of what femininity did, if that makes sense?"
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Image: My new life from Shutterstock.