The Pussycat Dolls singer is keen to start a family and has been discussing it with her Formula 1 racing driver partner Lewis Hamilton, who is also said to be keen to become a parent.
According to Britain's Hello! magazine, Nicole told a friend: "I'm mega broody and so is Lewis. Lewis tells me I would be the perfect mother."
Rumours have been circulating the pair have secretly got engaged and the couple are believed to be planning to announce their happy news in the coming months.
A friend of the 32-year-old singer revealed: "They plan to announce their engagement in the autumn. They want to wait until after the F1 season to make it official."
The couple briefly split in early January after 20 months together, with both blaming their hectic careers for the separation.
However, they got back together just a month later after realising they were still in love.
Nicole and Lewis are currently on holiday in Hawaii – where the singer was born – and have been having a great time paddle surfing, fishing and relaxing on the beach and are said to be "more in love than ever".