Forget the seven-year-itch. The new danger year for married couples is...

New research has shown it's the fifth year of marriage that really is the hardest. In fact most couples are lucky to make it to the infamous seven-year-itch zone at all.

According to the study released in the UK, a modern marriage goes something like this...

Year One: A whirlwind of wedded bliss;

Year Two: The ironing out of early issue;

Year Three: Smug happiness and comfortable co-existence;

Year Four: Cracks appear leading to disappointment;

Year Five: Tiredness, exhaustion and stress takes it's toll and most couples experience difficulties.

The study was conducted by family law firm Slater & Gordon. Lawyer Amanda McAlister told News Ltd the lesson from the 2000 surveyed couples is that marriage does indeed take effort. "It's not very often that we see clients in those first few years of marriage but by the five-year mark or a couple of years after they have children we often have married couples asking us for advice," she said.

It's a sad fact that most couples don't realise how hard marriage can be until they are in it. The biggest challenges most couples face in these early years are differing sex drives, hobbies and social preferences.

The study found that one in ten couples regret getting married all together and half don't consider their wedding day the best day of their lives.

McAlister said, "The buzz of the first few years where everything is new is hard to maintain and often people find that married life hasn't lived up to their expectations."

The good news is that if you do manage to get through this fifth year of marriage your chances of a long-term happy union increases.

Which has been the most difficult year of marriage for you and why?