"I was quite surprised by that email. I wasn't offended. I thought it was kind of funny that someone would have that opinion," she said.
The 42-year-old has since left the show for maternity leave.
In New Zealand, Lower Hutt resident John Rook wrote to TV Guide saying Clarkson, who is expecting twins, should be on maternity leave.
"I have no problem seeing pregnant women in normal situations or places, but to have them remain on TV in a state which I feel is embarrassing and an eyesore? It's time to replace them," he wrote.
He later apologised, which Clarkson accepted. She then explained her reasons for staying on screen on Facebook.
Clarkson took to Facebook to discuss her reasons for staying on air, and to thank those who had supported her decision to stay in front of the camera.
"To those who have chosen to write in support of me and my twins, thank you. As a heavily pregnant woman I struggle with my own demons about my body changing shape but I choose to stay in front of the camera to encourage others to be proud of the job that we are doing - creating life," she wrote.
- nzherald.co.nz