For the first time since records were first kept in 1749, Sweden's men now outnumber women in a worrying trend that could worsen in the decades to come.

The trend is highly unusual in the West, where women usually outnumber men, and began in March last year when data showed Sweden had 277 more men than women.

It is also likely to worsen - the current deficit in the Scandinavian country now sits at 12,000.

Groups of men gather outside Stockholm’s railway station as commuters hurry past. The influx of mostly male migrants has helped Sweden's male population increase beyond its female population

Official statisticians say the change - which is rare among Western countries - is also due to men's improving life expectancies

According to Valerie Hudson, the director of a program on women, peace and security at Texas A&M University, the change is one of the most dramatic she has ever seen, phys.org reported.

She added: 'Are people thinking about whether this could undermine the gains that have been made by Swedish women over the last 150 years?'

Official statisticians say the change is due to men's life expectancy catching up with women, while the influx of migrants from the Middle East and North Africa also tends to be mostly males.

Earlier this year figures revealed women can expect to live for less time in good health - while men should be in fine fettle for a little longer.

A baby girl born in 2014 could expect to have 64 years of life without suffering from a lifestyle limited by poor health - down from 64.2 years for those born between 2009 and 2011.

In the meantime, men who could expect 63.2 years in good health if born between 2009 and 2011 can look forward to 63.4 years if born between 2012 and 2014.

The analysis from the Office for National Statistics follows a narrowing of the overall life expectancy gap between men and women over the past decade.

Although women still live longer than men, the lifespans of men are growing faster than those of women.

The first recorded fall in the measures that show how long a woman can expect to enjoy full health appear to reflect the revolutionary changes over recent decades in the way that the majority of women live their lives.

ONS officials have previously pointed to the mass entry of women into work, which is thought to have led to higher levels of stress, alongside increases in drinking and smoking among women.

The healthy lifespan estimates follow new evidence earlier this week that women are having children at later and later ages.