Ms Childs said: "Prospect fully understands that this has been a very difficult time for our BTPS members.
"However, we have made some valuable improvements to the pension proposals in response to members’ concerns. We have also achieved a better pension and certainty for those already in the defined contribution BTRSS.
"Prospect will continue to keep pensions at the top of our agenda and seek to further improve BTRSS provisions wherever we can."
The CWU, which represents some of the 21,000 non-managerial staff of the company, is urging its members to say no to all changes being proposed by the telecom company.
In the meantime, BT announced last week that will be appealing the High Court decision against changing the index used for pension increases in its DB scheme.
BT was seeking approval to switch the rate used to calculate pension increases for about 80,000 members in BTPS, from the retail price index (RPI) to the lower consumer price index (CPI).
The case was taken to the High Court in December and concluded on 19 January, when it was decided the scheme’s underlying index could not be changed.