That's the main detriment to their careers, rather than having their performance devalued or being shortchanged during interviewing and hiring, researchers at Cornell University in Ithaca, N.Y., said.
"Motherhood -- and the policies that make it incompatible with a tenure-track research career -- take a toll on women that is detrimental to their professional lives," Cornell human development Professors Wendy Williams and Stephen Ceci said.
"Even just the plan to have children in the future is associated with women exiting the research fast-track at a rate twice that of men," they wrote in the journal American Scientist.
"It is time for universities to move past thinking about underrepresentation of women in science solely as a consequence of biased hiring and evaluation, and instead think about it as resulting from outdated policies created at a time when men with stay-at-home wives ruled the academy," Williams said.
The researchers analyzed data related to the academic careers of women and men with and without children and found that before becoming mothers, women have careers equivalent to or better than men's.
"They are paid and promoted the same as men, and are more likely to be interviewed and hired in the first place," Williams said.