Life may begin at 40 for men but for women this may not be the case. A new study has found that women feel they become invisible to men by the time they have turned 46.

A poll has found that once they hit their mid-40s, the fairer sex said men stop holding doors open for them and no longer offer to give up their seat on a crowded bus.

And that's not the only confidence crisis the 46-year-old has to deal with, as the arrival of a few grey hairs and a few extra pounds in weight makes her uncomfortable with the image she sees in the mirror.

The researchers found that women in their mid-40s also begin to fret that their views and opinions are no longer valid, and start to worry that their other half is ageing better than they are.

And by the time they reach their mid-50s, the majority of women say they no longer receive admiring glances from strangers or compliments from the opposite sex.

But the good news is that the dip doesn't last forever, with most regaining their confidence by the time they turn 60.

"Women are living longer and looking better than ever before, but it seems when they hit their late 40s and 50s, there is a definite period of adjustment. This research shows a lot of factors contributed towards making women feel invisible once they hit a certain age," the Daily Mail quoted Gareth Steer of Clarivu Total Vision Correction, which commissioned the poll of 2,000 women over 40, as saying.

"This coupled with the steady increase of over-50s requiring glasses for reading, shopping and driving add to that feeling of being older and more invisible," added Steer.