Women contribute around three trillion US dollars (£1.95 trillion) to global healthcare but nearly half of it is unpaid and unrecognised, according to a new study.

The report found that their involvement is undervalued economically, socially, politically and culturally.

Researchers attempted to estimate the financial value of women's contribution to health systems in 2010 by analysing data from 32 countries, accounting for 52% of the world's population.

They estimated the value of their paid work was 2.47% of global gross domestic product (GDP), while their unpaid work was 2.35% of GDP.

The total is equivalent to three trillion US dollars (£1.95 trillion).

The unpaid work is largely domestic care for family members, which is only officially acknowledged and compensated in a small number of countries, such as the UK, Turkey and Costa Rica.

Professor Ana Langer of Harvard TH Chan School of Public Health in Boston, USA, who co-led the commission on women and health, said: "Worldwide, most providers of healthcare are women.

"But the health systems to which they contribute so much are often completely unresponsive to their needs, despite the fact that they rely heavily on their paid and unpaid contributions.

"Women are undervalued and unsupported by the systems in which they work, and this problem is exacerbated by inequitable access to healthcare experienced by too many women worldwide - particularly those in the most vulnerable groups."

The work, published in The Lancet, is one of the most exhaustive studies on the relationship between women and healthcare. It involved heads of programmes, leading thinkers and activists from around the world.

The inquiry examined the links between biological, economic and social factors in improving women's health, including the effects of rapid globalisation, urbanisation and climate change.

Louise Silverton, director for midwifery at the Royal College of Midwives, said the findings demonstrated that women "need and deserve" more resources.

"Investment in women and girls through ensuring access to resources such as food and education has significant health benefits," she said.

"Girls who remain longer in education marry later, have fewer children, are less likely to die or be damaged as a result of pregnancy and birth and make greater financial contributions to their families.

"By not acknowledging women's unpaid contributions to family and community well-being, it is less likely that the often male dominated governments will allocate resources to women that they need and deserve.

"Improving access to education will also ultimately, and hopefully, lead to more women in positions of influence within these governments."