Cornwall GP Dr McCarron-Nash was elected back on to the GPC negotiating team at a committee meeting on Thursday.
Derbyshire GP Dr Peter Holden and Leeds GP Dr Richard Vautrey, deputy chairman of the GPC since 2007, retained their posts as negotiators.
They join Dr Dean Marshall, who is one year into a three-year term as a negotiator.
GPs challenged the BMA over the lack of female representatives in senior roles at the UK LMCs conference earlier this year. Dr McCarron-Nash's election, and that of Dr Charlotte Jones to chair GPC Wales, means the UK GPC will now have two female negotiators.
Earlier in the day, Dr Chaand Nagpaul was elected chairman of the GPC.
Dr Nagpaul saw off an all-women joint bid for the role by Londonwide LMCs chief executive Dr Michelle Drage and Birmingham GP Dr Fay Wilson, chief executive at out-of-hours provider Badger, who were knocked out in the first round of voting.
Dr Dean Marshall was eliminated in the second round, while deputy chairman Dr Richard Vautrey fell at the final hurdle.
Outgoing chairman Dr Laurence Buckman steps down from the GPC today after 16 years on the negotiating team and six years as chairman.
The unsuccessful candidates for negotiator positions are Devon LMC’s Dr Mark Sanford-Wood, Essex LMCs chief executive Dr Brian Balmer, and Gwent GP and former GPC Wales chairman Dr David Bailey.