Health visitors in Peterborough may be axed from the community and moved into a private "Social Enterprise" organisation.
Health trade union, Unite is worried that proposals to remove 75 health visitors will affect thousands of families with young children in the area.
Peterborough PCT are currently in the midst of a 3 month consultation to review a number of options, which also include health visitors working for the city council or becoming attached to the local NHS hospital trust.
Unite has warned that health visitors working for "social enterprise" organisations will not be covered by current NHS pay and pension conditions.
They say that Peterborough PCT has not provided health visitors with enough information to make "considered judgements" about their future employment.
"This move, if it goes ahead, could also have grave implications for families in Peterborough," said Unite Regional Officer Tony Ellingford.
"A 'Social Enterprise' firm may have a very tight contract with the PCT in the future which says health visitors will only provide certain services to the families that could be far less than what is currently provided.
"This would be a retrograde step and undermine the government's public health goals – and there are a number of deprived areas in Peterborugh which could lose out severely."
The final decision is expected to be made this autumn.