Years of real-terms cuts to child benefit and maternity pay have left new and expectant parents hundreds of pounds worse off - enough to buy a year's supply of nappies and babygrows, the TUC has claimed.
Research for the union organisation said a 1% increase in statutory maternity and paternity pay, adoption pay and child benefit from this weekend was a real-terms cut because it was below the rate of inflation.
The TUC said it was the fourth successive cut in the value of the benefits, which it claimed had led to new and expectant parents being £450 a year worse off.
General secretary Frances O'Grady said: "New babies are wonderful - but they can also be expensive, as any parent can attest. That's why it's important we protect the real value of family friendly benefits to give new parents the help they need to buy baby essentials.
"Family friendly benefits have come under stealth attack in every Budget since mid-2010. Successive years of real-terms cuts will leave expectant and new parents up to £450 worse off this year - enough to buy a year's supply of nappies, wipes and babygrows.
Belinda Phipps, chief executive of the National Childbirth Trust, said: "We strongly support this call for family-friendly benefits to increase in line with prices. This reinforces NCT research, published last month, showing that below-inflation increases to maternity and paternity pay mean new parents will lose out by £224 by 2015.
"These changes will hit families' finances hard at a time when they should be focusing on bonding with their new baby. We call on the Government to show that they value parents by increasing maternity and paternity pay in line with prices."