The 'Candy' singer became a father for the first time when Field gave birth to Theodora Rose on Tuesday (September 18).
Williams said that he has always been haunted by the 'Monday's Child' nursery rhyme which states that a child born on Wednesday is "full of woe".
"I was born on a Wednesday and Wednesday's child is full of woe," he told Greg James on BBC Radio 1.
"I was full of woe. I believed in the poem during my 20s."
The couple were glad their daughter was born on Tuesday, when children are said to be "full of grace".
Williams also revealed that he is going to attempt swearing less now that he is a father.
"I do have a potty mouth, I really do. I am going to have to curb it."
Robbie Williams has also confessed that he is jealous of One Direction's worldwide success.
Watch the video for Robbie Williams's 'Candy' below: