Ciara and Russell Wilson
NFL Player Russell Wilson and musician Ciara attend the Warner Music Group GRAMMY Party at Milk Studios on 12 February Joshua Blanchard/Getty

American singer Ciara is expecting her first baby with husband Russell Wilson. The couple have kept the gender of their soon-to-be-born child a secret but it now appears the singer is teasing her fans with cryptic Instagram posts to guess whether it's a boy or a girl.

The couple recently attended the Warner Music Group GRAMMY party at Milk Studios in Hollywood and the singer posted a picture of herself on the image sharing website. The 31-year-old singer can be seen wearing a powder blue and white pyjama-inspired oversized coat. She complemented her look with a black top and trousers. She captioned the image: "Blue is one of my favorite colors."

The R&B songtress is nearing her due date and her cryptic hint has led many to speculate that she is expecting another boy. The 1, 2 Step singer is mother to Future Zahir, her two-year-old son who she shares with her ex, Future.

But this is not the first time she has worn blue. Since the announcement of her pregnancy, Ciara has been spotted wearing blue ensembles several times, combined with her favourite black and whites, which she wore occasionally.

While the Goodies album hitmaker is yet to respond to rumours, fans are decoding the colour of her regular wardrobe to mean she is expecting a son with her NFL quarterback.

Ciara and Wilson started dating in 2015 and got married on 6 July in Liverpool, England. They announced the pregnancy in October 2016.

The guessing game will continue until the couple reveal the gender before or after the arrival of baby Wilson. In November 2016, the singer revealed to ET Online that her son is excited to welcome his sibling. "He rubs my belly and he says, 'Hi baby. I love you, baby,' ... and then he puts my shirt down and says, 'Bye, bye baby.' So, that's his own thing. He sees a baby walking, smaller than him and walking -- it doesn't matter, it's a baby. So, he goes, 'baby' and he looks at me and he goes, 'Mama, baby' --and he tries to pull my sweatshirt up."