Women, young people and parents of children under five have been hardest hit psychologically by the Covid-19 lockdown, research suggests.

A new study found 27% of people in the UK were experiencing clinically significant levels of psychological distress in April, compared with 19% before the pandemic.

A General Health Questionnaire (GHQ) assessing the severity of a mental health problem over the previous few weeks also showed increasing distress across the population in April.

The 12 questions included how often people experienced symptoms such as difficulties sleeping or concentrating, problems with decision-making or feeling overwhelmed.

Increases were bigger in some groups compared to others, with a 33% rise among women, 32% among parents with young children and 37% among young people aged 18 to 24, the study found.

Policies emphasising the needs of women, young people, and those with pre-school aged children are likely to play an important part in preventing future mental illness

People who were employed before the pandemic also averaged a notable increase in their GHQ score.

The 17,452 people in the study were taking part in the UK Household Longitudinal Study (UKHLS) and were aged 16 and over.

The research, published in The Lancet Psychiatry, included a team from the University of Manchester, King’s College London, City University and the National Centre for Social Research.

The researchers concluded: “By late April, 2020, mental health in the UK had deteriorated compared with pre-Covid-19 trends.

“Policies emphasising the needs of women, young people, and those with pre-school aged children are likely to play an important part in preventing future mental illness.”

Sally McManus, joint senior author of the study from City University, said: “The pandemic has brought people’s differing life circumstances into stark contrast.

“We found that, overall, pre-existing inequalities in mental health for women and young people have widened.

“At the same time new inequalities have emerged, such as for those living with pre-school children.

“These findings should help inform social and educational policies aimed at mitigating the impact of the pandemic on the nation’s mental health, so that we can try to avoid a rise in mental illness in the years to come.”

Dr Matthias Pierce, from the University of Manchester, said: “We estimate as many as 44% of young women are experiencing clinically significant levels of mental distress compared with 32% before the pandemic.

“It appears to be the mental health of the young and of women that is disproportionately affected by Covid – this may flow from the Government’s pandemic response and strategies to mitigate transmission of the disease.

“The higher mental distress in women widens established mental health inequalities and highlights how important it is that providers make sure to maintain people’s access to services for domestic violence, sexual and reproductive health. Availability of childcare is also urgently needed.”

The team did not find significant deterioration in mental health in men and the over-45s.

However, they said further studies should examine ways that men may express distress, for example through addictions to alcohol or gambling.