Halsey was rushed to hospital after suffering a "minor medical emergency"

She wrote on her Instagram Story: "Boston I'm gonna be honest with ya, after the show last night I was in the ER till 6 this morning.

"Minor medical emergency but I am A-Okay now and ready to rock tonight. But if I'm pacing myself, that's why!

"Huge shout out to Mass General and Dr Kian, Dr Victoria and my nurses Carolyn and Alicia for being the absolute best team I've ever met.

"And I second that with regard to the imaging staff, transport team, and patient relations!!! I am so so grateful!

"LETS ROCK TONIGHT! (sic)"

Halsey returned to the MGM Music Hall at Fenway, Boston for the second of two shows at the venue as part of her Back To Badlands Tour.

The Ego hitmaker didn't reveal what the nature of the medical emergency was.

She revealed a different health update in September, having undergone chemotherapy after she was diagnosed with Lupus SLE and a rare T-cell lymphoproliferative disorder back in 2022.

She said on TikTok: "Just coming on here to give you guys another speed round of updates. [I] just did another few sessions of chemo.

"[I] had a new port placed.

"We just put the Back to Badlands show together, and it's going to be unbelievable; so amazing. My birthday's in a couple of days. I'm so busy, I haven't even thought about it at all."

According to the Cleveland Clinic, a chemo port is a "small, implantable device that attaches to a vein" typically in the upper chest area.

The institution says: "It allows healthcare providers to draw blood and give treatments - including chemotherapy drugs - without a needle stick.

"A port can remain in place for weeks, months or even years."