It's Valentine's Day and as Australians put the finishing touches to gifts, serve brekkie in bed or practise that proposal, new relationship research may be about to burst a few love myths like Cupid's arrow shot into a heart.

A survey of more than 2000 people in marriages and de facto relationships by law firm Slater and Gordon found young love was the bumpiest of all.

"More than three quarters, or 77 per cent, of couples aged between 25 and 34 admitted that there are issues that need fixing in their marriages," family lawyer Heather McKinnon said.

"In comparison, just over half of couples surveyed who are aged over 55 said there were no issues that needed addressing in their marriages," she said.

Ms McKinnon said the honeymoon had definitely passed for a large number of newlywed couples.

"Many of these couples have not been married for very long," she said.

"Of those who have been married for just two to three years, a staggering 82 per cent said their relationships need improving."

Ms McKinnon said the research was further evidence of a world-wide trend known as "starter marriages".

"Sadly, in Australia more than 40 per cent of divorces happen before a couple reaches their 10th wedding anniversary. The highest divorce rate is among those aged 25 and 34."

Other heart-breaking relationship statistics include:

• Almost two thirds, or 63 per cent, of all couples surveyed admitted there were issues in their current relationships they believed need improving.
• Almost half, or 47 per cent, said their sex lives needed attention
• 44 per cent nominated overall intimacy was an issue
• 43 per cent said they wanted less focus or strain on finances
• 39 per cent believed they didn't spend enough time together.
• Most men (58 per cent) of those surveyed said they would like to see improvements in their sex lives, while 46 per cent of women cited financial issues as their biggest concern.