AceShowbiz - Pop star Halsey is set to become a first-time mother.

The "Without Me" hitmaker shared the shock announcement via Instagram on Wednesday (27Jan21) as she posted a trio of maternity photos, in which she showed off her growing belly, with two images featuring herself topless.

"Surprise!" she simply captioned the shots, adding emojis of a baby bottle, a rainbow, and an angel baby. The rainbow icon is a nod to her previous miscarriages, one of which she suffered while on tour in 2015.

Halsey, who struggles with uterus tissue disorder endometriosis, tagged screenwriter Alev Aydin in the snaps, suggesting he is the father of her child. He fuelled the speculation by reposting one photo on his Instagram Story timeline and adding two red heart emojis.

Halsey's followers were quick to offer up their well wishes with actress pal Ruby Rose commenting, "Wow wow wow! Congratulations."

It's unclear how long Halsey and Aydin have been dating, but she was previously in an on/off relationship with rocker Yungblud until last year (20) and dated rapper G-Eazy for a year before parting ways in 2018.

Back in 2016, Halsey revealed she lost her unborn baby because she's overworked. "I beat myself up for it," she lamented, "Because I think that the reason it happened is just the lifestyle I was living. I wasn't drinking. I wasn't doing drugs. I was f**king overworked - in the hospital every couple of weeks because I was dehydrated, needing bags of IVs brought to my greenroom. I was anemic, I was fainting. My body just broke the f**k down."

She added, "I want to be a mom more than I want to be a pop star. More than I want to be anything in the world. I'm really scared of being alone. I'm not trying to upset you. I'm really sorry."

The singer then revealed in 2019, "I have endometriosis. I've had 3 miscarriages, 4 surgeries, pretty much in pain every day of my life."