Singer Rihanna is pregnant with baby number three.

The pop icon, 37, seemed to be trying to cover a baby bump as she left the Carlyle Hotel ahead of this year’s Met Gala in New York on Monday, US time.

The singer and her partner, rapper A$AP Rocky, already have two sons — Riot Rose, 21 months, and RZA Athelston, who turns three this month.

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The singer’s photographer Miles Diggs later shared a photo of her walking in the rain, clearly showing her baby bump, on Instagram.

The singer was eye-catching in a skirt and long-sleeve top ensemble with matching stockings and heels. She finished her vintage look with a string of pearls and a 1920s-style black cloche hat.

The theme for this year’s Met Gala at the city’s Metropolitan Museum of Art is Superfine: Tailoring Black Style.

Sunrise stylist Elliott Garnaut on Tuesday said Rihanna is “no stranger to announcing a pregnancy in a public sphere, obviously”.

“The last pregnancy was announced at the Super Bowl, so I can’t wait to see what she actually wears on the red carpet and how she dresses up that bump because sometimes she covers it all up and other times it’s out on show,” he said.

“So, Rihanna, the icon she is, I can expect nothing but perfection.”

In an interview with Page Six, Rhianna previously spoke of how her relationship changed when she and Rocky became parents.

“I love him differently as a dad. This is major, major ... it’s a turn on,” she told the publication.

“It’s just like, wow, what a leader, what a great, patient loving ... and my kids are obsessed with him.”