Britney Spears is pregnant with third child, Instagram post suggests

Spears expressed a desire to have more children last year,

Telling a judge she was not able to make her own birth control decisions under conservatorship.

Announcement comes after singer was released from conservatorship she says required her to stay on birth control

Spears had previously shared that she “wants a family” with the fitness model, 28

Britney Spears is pregnant, the 40-year-old pop star announced on Instagram Monday.

Spears wrote in her post that shortly after a trip to Maui with her fiancé, Sam Asghari, she started to gain weight.

She wrote, "So I got a pregnancy test ... and uhhhhh well ... I am having a baby."

Spears has two teenage sons, Sean and Jayden, with former husband Kevin Federline.

Spears referred to Asghari as her husband, but it was not immediately clear if they had married..