United Kingdom, April 5 -- Shakira is convinced her singing voice totally changed after her pregnancies.

The pop star is a mum to two sons with her ex Gerard Pique and she believes that giving birth to her boys had an effect on her voice making it sound "thicker" and "more rounded".

During an appearance on YouTube show 'Hot Ones', she explained: "I noticed that after my pregnancies, my voice got thicker, more rounded, more full. "Also, my choices are more mature. I have evolved as a woman, as a person, my intellect has evolved."

She also admitted listening back to some of her early tracks makes her "cringe" because she used her trademark yodel too much. Shakira added: "I think I used to overdo the cries in my voice. I think it was exag...