TVNZ One News 31 January 2016
The much-contested bill was presented to parliament last week and is due to be voted on in February.
But the government itself is deeply divided over the issue and opponents are hopeful they can sink it, as they have done in the past.
Trains and buses ferried in protesters from around Italy to take part in the event, staged in Ancient Rome’s famed chariot racing stadium.
“We want the whole law to be withdrawn, no ifs and no buts,” said one of the organisers, Simone Pillon.
“We cannot let children pay for the desires or caprices of adults… Children need to have a father and a mother.”
Organisers said they expected more than half a million people would join the Circus Maximus rally, but official numbers were not immediately available.