The agency has been asked to handle a public affairs and PR campaign following a competitive pitch.
Bounty has 2.1 million members and more than 50,000 joining every month. It has approximately 95 per cent market coverage of the estimated 750,000 annual births in the UK.
Munro & Forster will target stakeholders, politicians and the media as part of the brief to build Bounty's position as the authoritative voice of parents.
The company announced earlier this year it was taking its comms support in-house and hired its first head of PR (PRWeek, 18 April).
Lisa Penney joined from B2B agency Nobull Communications, where she spent three years as associate director.
Penney said: 'Bounty is incredibly well known, respected and trusted among UK parents.
'Yet it wishes to achieve a increased understanding of the role Bounty plays in supporting the health service and young families in the UK.'
She added: 'Part of what we do is getting parents involved online and we are like the Facebook alternative for parents. But we are also try- ing to communicate to the Government what parents think.'
Bounty also has an online community of 800,000 uni-que users, a fifth of whom spend 12.5 hours a week seeking advice and tips.