New mothers are to be offered up to £200 in shopping vouchers to encourage them to breastfeed their babies.
The pilot scheme is being targeted at deprived areas of South Yorkshire and Derbyshire and funded through a collaboration between government and the medical research sector.
A third area is expected soon with the plan to trial it on 130 women who have babies from now until March.
If successful, a nationwide pilot could be rolled out in England next year.
The use of financial incentives is not new in the NHS.
It has been tried before to encourage people to quit smoking as well as lose weight.
But this is the first time it has been tried on such a scale for breastfeeding.
Under the scheme mothers from specific parts of Sheffield and Chesterfield will be offered the vouchers, which they can then use in supermarkets and high street shops.
The areas have been chosen because they have such low breastfeeding rates. On average just one in four mothers are breastfeeding by the six- to eight-week mark compared with a national average of 55%.
To qualify for the full £200 of rewards, the women will have to breastfeed until six months.
However, it will be frontloaded - enabling those taking part to get £120 for breastfeeding for the first six weeks.
Midwives and health visitors will be asked to verify whether the women are breastfeeding.
The team behind the project said breastfeeding was a cause of health inequalities, pointing to research that showed it helped prevent health problems such as upset stomachs and chest infections as well as leading to better educational attainment.
Dr Clare Relton, the Sheffield University expert leading the project, said she hoped the financial incentives would create a culture where breastfeeding was seen as the norm.
"It is a way of acknowledging both the value of breastfeeding to babies, mothers and society," she added.
But Janet Fyle, of the Royal College of Midwives, questioned the initiative: "The motive for breastfeeding cannot be rooted by offering financial reward. It has to be something that a mother wants to do in the interest of the health and well-being of her child."
She said the answer lay in making sure there were enough staff available to provide comprehensive support to new mothers after birth.