A study into "breast habits" by US experts suggests that revealing clothes actually put off males colleagues, and even take a toll on a woman's career prospects.
They found that many working women were swapping their power-suits for more feminine, form-fitting clothes, such as scoop-neck tops and V-neck jumpers teamed with skirts.
American author Elisabeth Squires, nicknamed "The Boob Lady" on US TV, has commissioned the study.
"Breasts are getting bigger but clothes seem to be getting smaller, especially in the workplace," the Daily Express quoted Squires, author of 'Boobs: A Guide To Your Girls', as saying.
"A layered style of tight shirts seems to be a major fashion trend fuelled by a look that is very popular in European offices. But what looks great on a 20-something female can look ridiculous on a 40-year-old," she added.
The researchers found that displaying too much flesh in the office could be distracting, and even damage a woman's career.
Men who participated in the study were shown photographs of women in a generic workplace in various outfits, and with different bra sizes.
When asked which of the women looked the most professional and personable, most men picked out "discreetly dressed" women with "medium-sized breasts".
According to Squires, showing a small amount of cleavage is OK for some women with good figures, and can help propel their careers.
"To look really great in this kind of 'showy' clothing, you have to have an almost perfect figure. But let's face it, most of us don't," she said.
"Walk around any public place and you will see women with the tell-tale muffin top spilling over too-tight pants and a low-cut top.
"And even for those with perfect figures, there is a question of when to use breast power. But the appearance of a small amount of breast can look really great," she added.
However, Squires warned that no woman should allow herself to "be defined" by her breasts.