Some pool users in Leics want a change in rules that can stop a parent taking all their children into the water.
Pool managers in Charnwood can ban two or more children under four years of age swimming with a single parent.
Guidelines also mean that, depending on swimming ability, no more than two children under eight should be allowed into a pool with a single parent.
Loughborough MP Andy Reed wants the rules changed so parents can take all their children.
'Morally wrong'
Apart from standard health and safety laws, most safety rules are just guidelines and it is up to individual pool managers to interpret them.
But some parents have said this means single parents, or those with larger families, cannot go swimming together.
Ralph Riley is the chief executive of the Institute of Sport & Recreation Management which drew up the guidance for pool managers.
He said: "There are an awful lot of children that are being allowed to go to swimming pools unaccompanied.
"That is an issue because quite a few times, at quite a few swimming pools, they were almost being used as a baby sitting service and morally that was wrong."