Prince William's wife Kate laid bare her "mummy guilt" during a landmark podcast on Saturday, recorded as part of her efforts to bring about a "generational change" in early-years childcare.
The duchess told the "Happy Mum, Happy Baby" podcast that she suffered anxiety about her performance as a mother "all the time", adding that "anyone who doesn't as a mother is actually lying".
"Questioning your own decisions, and your own judgements, and things like that... I think that starts from the moment you have a baby," said the mother-of-three.
"I totally underestimated the impact and the change it had on our lives.
Asked if she felt "mummy guilt", the duchess -- mother to George, aged six, Charlotte, four and Louis, 20 months, responded -- "yes, absolutely".
She said she "definitely would have done things different... knowing what I know now" referring to her first pregnancy with Prince George.
The morning sickness that she suffered with all three of her children had strained the family, she said.
"William didn't feel he could do much to help and it's hard for everyone to see you suffering without actually being able to do anything about it," she explained.
Despite the challenges, she said that since having children she had "found a new enjoyment out of life".
Her experience of bringing up three children have led her to launch an early years survey to help find answers about raising a "happy, healthy" generation.
"I think there's a few things that really stand out for me," she said.
"One is quality of relationships -- so those moments that you spend with people that are around you. I remember that from my own childhood.
"I had an amazing granny who devoted a lot of time to us, playing with us, doing arts and crafts and going to the greenhouse to do gardening, cooking with us, and I try and incorporate a lot of the experiences that she gave us at the time into the experiences I give my children now," she added.
When asked what she hopes her children will remember from childhood, Kate replied: "Going to the beach getting soaking wet, filling our boots full of water."
Kate has previously spoken of worrying about how well she was adapting to motherhood, saying "it is lonely at times and you do feel quite isolated".