Halsey pregnant with her first child

Halsey took to social media on Wednesday (Jan 27) to reveal she is expecting her first child, as she shared a picture of her burgeoning baby bump.

She wrote on Instagram: "Surprise!", alongside a series of emojis, including a baby's bottle, a rainbow, and an angel.

The news will come as a shock to many of Halsey's fans, as the 26-year-old singer was not thought to be dating anybody prior to her pregnancy announcement.

However, she tagged screenwriter Alev Aydin in her Instagram post, suggesting he is her mystery beau, and the father of her unborn baby.

As of the time of writing, Alev has not yet commented publicly on the news.

Halsey also posted about her pregnancy on Twitter, where she referred to her impending arrival as her "rainbow baby", which is a term often used to describe a baby who arrives after a miscarriage or stillbirth.

The singer - who was diagnosed with endometriosis in 2016 - has previously been open about her experience with pregnancy loss, as she said she once suffered a miscarriage while in the middle of a concert.

She said in 2018: "I was on tour, and I found out I was pregnant. Before I could really figure out what that meant to me and what that meant for my future... the next thing I knew I was on stage miscarrying in the middle of my concert.

"The sensation of looking a couple hundred teenagers in the face while you're bleeding through your clothes and still having to do the show, and realising in that moment... I never want to make that choice ever again of doing what I love or not being able to because of this disease.

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"So I put my foot down and got really aggressive about seeking treatment and I had surgery about a year ago and I feel a lot better."

And last year, Halsey said the experience made her feel "inadequate".

She explained: "It's the most inadequate I've ever felt. Here I am achieving this out-of-control life, and I can't do the one thing I'm biologically put on this earth to do. Then I have to go onstage and be this sex symbol of femininity and empowerment? It is demoralising."