Adverse childhood experiences in firstborns associated with poor mental health of siblings

Children are nearly three-quarters (71%) more likely to develop mental health problems between the ages of five and 18, if the firstborn child in their family experienced adversity during their first 1,000 days, finds a new study led by UCL researchers.

The first-of-its-kind study, published in The Lancet Public Health and funded by the National Institute for Health and Care Research Policy Research Programme, found that mothers whose firstborns had experienced adverse childhood experiences had a 71% increased risk of having children (aged five -18) with mental health problems, compared to mothers whose firstborn did not experience adversity.

This translates to 12 additional children with mental health problems for every 100 mothers whose firstborn experienced adversity.

These findings underscore the pervasive risk that early adversity can have on multiple children in the family, and the importance of early identification and sustained support for vulnerable families beyond the first 1,000 days of a child's life.

As part of the study, researchers analysed linked GP and hospital health records from 333,048 first-time mothers and their 534,904 children (firstborns and siblings) born in England between 2002 and 2018. They focused on six different forms of adverse childhood experiences in the firstborn child recorded during their first 1,000 days of life (from conception up until the age of two).

These included: child maltreatment, intimate partner violence, maternal substance misuse, maternal mental health problems, adverse family environments (e.g. homelessness), and high-risk presentations of child maltreatment (e.g. unexplained child injuries).

Over a third (37.1%) of firstborn children had at least one recorded adverse childhood experience. The most common adverse childhood experiences were living with maternal mental health problems (21.6%), followed by adverse family environments (14.5%) such as parental criminality and housing instability.

Approximately one in five (19.8%) mothers had at least one child with a recorded mental health problem between the ages of five and 18.

Mothers whose firstborns experienced adverse childhood experiences had significantly more children with mental health problems (average of 30 per 100 mothers) compared to mothers whose firstborns did not (average of 17 per 100 mothers).

The risk of mental health problems was consistent across all siblings, regardless of birth order (firstborn vs thirdborn), in families where the firstborn experienced adverse childhood experiences.

Children in families where the firstborn experienced adversity also had 50% more emergency hospital admissions for any reason and double the amount of mental health-related healthcare contacts.

Lead author Dr Shabeer Syed (UCL Great Ormond Street Institute of Child Health), said: “Whilst previous research has focused on the impact of adverse childhood experiences on individual children, our study reveals a cascading health risk that extends beyond the individual, impacting on the health of siblings as well.

“This likely stems from the continuation of adverse childhood experiences within the family. When a child or parent presents with mental health concerns, violence or other forms of adversity, it's essential to ask about the wider family context.”

Professor Jessica Deighton (UCL Psychology & Language Sciences, and Anna Freud, a mental health charity for children and young people) said: “With escalating rates of children and young people in contact with mental health services, early and effective prevention strategies are the key to improving wellbeing. These findings indicate that, when we encounter children facing significant challenges like domestic abuse or poverty, we must expand our focus to the whole family, including siblings. This would help to ensure all children and young people within families dealing with adversity receive appropriate care as early as possible.  

“To achieve this, we want to see increased funding for prevention schemes and harness community assets – such as GPs and local organisations - which are crucial for helping to identify and meet the needs of vulnerable young people. There should also be, in partnership with diverse groups of children and young people, the development of a comprehensive, cross-government mental health prevention strategy.” 

As a result of their findings, the team are also calling for further research into the impact of early health visiting and primary care support.

Senior author, Professor Ruth Gilbert (UCL Great Ormond Street Institute of Child Health), said: “Prevention of childhood mental health problems through intensive support in early life for parents and their first and subsequent children could potentially benefit multiple family members.

“Research is needed to assess whether early community support from health visitors, GPs and practical parenting support for families whose first or subsequent children are affected by adverse childhood experiences reduces mental health problems later in childhood.”

Co-author, Professor Gene Feder (University of Bristol Centre for Academic Primary Care), said: “General practice teams have a key role in identifying first-born children experiencing adverse childhood experiences and in supporting first-time parents to help reduce the impact of adverse childhood experiences on the whole family, including subsequent children.

“We need further evidence for effective interventions to reduce that impact, particularly on mental health.”

Study limitations

The researchers could not investigate adverse childhood experiences related to fathers’ mental health or substance use as healthcare data from fathers could not be linked to their children.

The study found that adverse childhood experiences in firstborns were associated with mental health outcomes in the first and subsequent children, but this does not necessarily mean that adverse childhood experiences cause mental health problems.

Additionally, electronic health-care records underestimate intimate partner violence and child maltreatment due to non-disclosure and/or detection and under-recording by clinicians.