Melbourne: ‘Sex and the City’ syndrome is being blamed for causing the breakdown of a growing number of Australian marriages, a new study suggests.

In a seismic shift from a decade ago, family lawyers say more men are pointing to their wives' excessive drinking and drug use when filing for divorce, with an increasing number of husbands being awarded sole custody of their children because of it, website reported.

Senior family lawyer at Slater and Gordon, Heather McKinnon, said that about 30 percent of the firm's cases before the Family Court involved substance abuse.

Of these, about half now related to the female partner, something that was "practically non-existent" 10 years ago.

"That's a really huge shift in my lifetime in the job," she said.

"Dads that have applied to have children living with them are now succeeding in about half the cases, and that's because there's deficits in the mother. I think this is a very serious shift," she added.

McKinnon points the finger at so-called " Sex and the City syndrome" - the normalisation of binge drinking among teenage girls and young women that carries through to adulthood.

"If you go to any social setting in a capital city or a large regional town on a Friday or Saturday night you will see young women at the bar downing shots - that is a generational change," McKinnon said.

"Girls are at an early age starting to abuse alcohol, they drink heavily through their twenties and by their early thirties they've become fully-fledged alcoholics. They don't stop drinking when adolescent experimentation is finished," she said.

The 2010 National Drug and Alcohol Household Survey shows that while men overwhelmingly drink more than women, the number of women aged 20 to 29 drinking at risky levels increased between 2007 and 2010, while girls aged 12 to 17 outdrink boys by one-and-a-half percent.