Israel says that any Palestinian suffering from a genuine medical emergency is allowed to cross checkpoints in order to get to hospital.
But many Palestinians live in fear of an unforeseen health crisis – particularly at night or when they are somewhere far from medical attention – which would mean that they would have to travel through a number of checkpoints to get to hospital.
According to the Israeli human rights group B'tselem, there have been at least 38 cases since September 2000 of Palestinians who have died after medical care was delayed as a result of Israeli restrictions of movement.
An Israeli army spokesman told BBC News Online that soldiers only began checking ambulances during the intifada.
He said that there have been incidents in which ambulances have been used to carry healthy, wanted Palestinians, and that in one case an explosive belt was found in an ambulance carrying a sick child.
He said that checks are done quickly.
At unmanned roadblocks which ambulances cannot pass, young Palestinian volunteers often help the sick and disabled by pushing them across in wheelchairs.