E tūtaki ana ngā kapua o te rangi, kei runga, kei runga te Mangoroa e kōpae pū ana | The clouds in the sky close over, but above them spreads the milky way

Growing Up in New Zealand is a longitudinal study tracking the development of approximately 7,000 New Zealand children from before birth until they are young adults.


The study has collected detailed multidisciplinary information about children’s early development from before they were born, and reflects the diversity of today’s pre-school children: one in four children in the cohort identify as Maori, one in five as Pacific Islander, one in six as Asian and two out of three as European. Nearly half the children identify with more than one ethnic group.

GUINZ; most children ok but some are not


Growing Up in New Zealand (GUINZ) is a New Zealand cohort study of 6,853 children recruited during pregnancy, represents the current New Zealand birth population, and followed for eight years so far.¹,²


  • 80% of children are doing well according to their mothers, and 20% not doing so well.


  • 12% of pregnant women suffer postnatal depression symptoms, and 8% in their child’s first year of life. 20% get professional help.


  • 5% of male partners also had postnatal depression symptoms, and commonly this increased the chances their partners also did.


  • Bullying is reported by mothers of 33% of pre-schoolers, and by the children themselves at 8 years. 35% report being bullied regularly (14% weekly).


  • 4% of children witness their parents’ physical violence, and 10% witness their parents’ psychological violence.


  • 5% of the children have moved house at least once before they are eight years old.



Growing Up in New Zealand is designed to provide unique information about what shapes children’s early development in contemporary New Zealand and how interventions might be targeted at the earliest opportunity to give every child the best start in life. A key aim of the study is to provide evidence to inform policy development, for example whether existing government policies are reaching the families they were designed for and, if so, what effect they are having. This can inform the development of new strategies better targeted to address entrenched problems.


Early information from Growing Up in New Zealand provides insight into areas like vulnerable children, housing, breastfeeding/early solids, immunisation, languages, early childhood education, interaction with health and other key services, paid parental leave and maternal return to the workforce.


Growing Up in New Zealand is University of Auckland-led research and funded by multiple government agencies. The government contract for the study is managed by the Families Commission.

Read more here: Unmet Mental Health Support for Pregnant New Zealand Women (15 July 2021); The first-ever study to look at anti-depressant use and symptoms of depression in pregnant New Zealand women has identified unmet need for antenatal mental health support.


  1. Susan Morton: Growing Up in NZ 2021  View on YouTube
  2. Now we are eight. GUINZ (2021) View pdf