New parents run up an average debt of £1,140 before the baby turns one, new research has discovered.
MoneyExpert.com warns a combination of increased costs and loss of earnings can see parents plunging into the red.
Seven per cent of new parents find themselves indebted by £2,500 after a year and one in 50 owes above £7,000.
The research discovered 39 per cent of couples have to cope with a smaller income as one reduces their hours or gives up work entirely to care for the baby.
Sean Gardner, chief executive of MoneyExpert.com, said many parents disregard money worries as they enjoy the addition to their family and cope with the new responsibilities.
"If money is already tight, its no wonder that so many families have had to turn to borrowing to make ends meet," he commented.
The government warns that ignoring money problems in order to cope with the demands of a baby can be self-defeating as financial worries can add to pressure and cause ill health through stress.