In response to a sea of encouraging messages on Instagram and Twitter, the singer, 26, shared a message of gratitude to their millions of followers.
'thank you,' the star, who is expecting their first child with boyfriend Alev Aydin, wrote along with a red heart emoji on Saturday afternoon.
The Grammy nominee's pronouns signify she identifies as a woman, but also non-binary.
'It actually rocks for Halsey to come as she/ they while heavily pregnant,' one Twitter user praised.
Another gushed: 'Halsey She/They!!! Proud of them!!!!'
Meanwhile, an additional fan tweeted, 'If you don't support Halsey for being she/ they please let me know, so I can block you.'
Halsey updated fans on her pregnancy last month with an Instagram slideshow of her changing body.
'it's strange to watch yourself change so quickly. I thought pregnancy would give me strong, binary feeling about 'womanhood' but truly it has leveled my perception of gender entirely. My sensitivity to my body has made me hyper aware of my humanness and that's all,' she wrote in the lengthy caption.
'Doing a remarkable thing. And it's grand. I hope the feeling lasts,' she added.
Halsey and Alev 'have been dating for several months' but she 'has been low-key about their relationship, a source previously told People, following the couple's pregnancy reveal.
'They were spending a lot of time at her house in the fall though, and it was obvious that she was happy,' the insider dished.
Over the summer Halsey and Alev got matching foot tattoos that featured the word 'Seeds' in black ink.
