The breasts are a cheaper alternative to latex models
Health officials in Leeds have launched an unusual appeal - for fake breasts.
They are seeking people to knit breasts in all shapes, sizes and colours to be used for teaching expectant mothers.
Health visitors at present have to demonstrate breastfeeding using balloons or their own elbows, which they say are less than realistic.
Their website provides a pattern for crocheting or knitting the breasts, approved by the Lactation Consultants Association of Great Britain.
Sally Mills from Leeds Primary Care Trust said they would make a contribution to a charity of the knitter's choice if they received any woollen breasts from the public.
"The only place we could get them from was Australia and they were £20 each," she said.
"This way people can enjoy a laugh making them, and help us at the same time."
The breasts are welcomed in a variety of skin shades.
The website also says: "It is good to have a variety of shapes and sizes, just as women do (very flat, very small/large, inverted etc)."
They are also used by community midwife teams to demonstrate how milk should be expressed, particularly for premature babies being kept in hospital.
A similar appeal in Liverpool in 2007 produced offers from all over the world.