More than half of those surveyed said they took time away from their children to "maintain their sanity.''
Auckland-based parent coach Kristina Patterson said she was not surprised by the findings, having dealt with many women who had found it hard to adjust to motherhood.
"It is a real problem. There's the guilt and the isolation. A lot of mothers don't realise that there's a new adjustment to be made,'' she said.
"It can be just a real shock for people.
"Some women are great. They take on motherhood fine. But for others, there's an adjustment period that they go through and it's very difficult.''
Psychologist Sara Chatwin said many New Zealand women ended up feeling exhausted and isolated because of the expectation that they were able to do everything.
"Societal expectations also seem to create pressures for mothers to offer children all the options and again, this can present challenges to achieve on a daily basis.''
Other findings in the survey show that 45 per cent of mothers felt they were worse off than generations before them.
Twenty-three per cent said today's children required more supervision, and 18 per cent said they were spending more time helping their children with their homework because of an increasing amount.
As a parent coach, Ms Patterson goes into a family's home and observes how parents interact with their children and then helps to resolve any issues that arise.
Her work led to the establishment of the Mothers Helpers charity, which aims to help mothers who have post-natal depression.
Acknowledging the findings, she said women felt guilty for all sorts of reasons and many began feeling so even early in their pregnancy.
"There's often many things that can make you feel that guilt. [Like] whether or not they stayed home long enough, feeling bad about going to work, whether they exercised when they were pregnant.
"There's so many expectations women face and it's very hard when you think you can't live up to them,'' she said.