The pressures of running an academic lab and spending late-nights writing grant proposals make the choice between motherhood and having a career in science tough. Even after getting advanced degrees in science and math, many women drop out of research careers primarily because they want children, finds a new study.

The researchers also found choosing motherhood over academia seemed to have little to do with any gender-inequality issues, perceived or otherwise.

"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," researchers Wendy Williams and Stephen Ceci, of Cornell University, reported in the March-April issue of the magazine American Scientist, "This reality is too daunting for some women, and they either leave the tenure-track pipeline or give up on having children."

(Many full-time academics work toward a "tentured" position, which offers much greater job security; though they still need to attain funding for their research, their institution can't fire them from their position without just cause, like making up data.)

In the top 100 U.S. universities, women held 4.4 to 12.3 percent of the institutions' full professorships and just 16 to 27 percent of assistant professorships in math-intensive fields such as physics, chemistry and engineering.

Women in science

For the report, Williams and Ceci reviewed data on the academic careers of women and men with and without children in academic fields. They 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 in a statement. This is even true at high-level professor positions, but, after the mommy-bug hits, many women stall out.

"The effect of children on women's academic careers is so remarkable that it eclipses other factors in contributing to women’s underrepresentation in academic science," the authors write. "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."

Changing policy

The researchers suggest various policies in university science departments are unforgiving to female professors wanting children, and may be behind the dropout rate. These are solvable problems, though. Williams and Ceci suggest focusing on alleviating the pressures on mothers while they are working toward tenure by, for instance, creating a part-time tenure track or allowing more freedom to work from home.

"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 in a statement.

You can follow LiveScience staff writer Jennifer Welsh on Twitter @microbelover. Follow LiveScience for the latest in science news and discoveries on Twitter @livescience and on Facebook.

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