Gender barriers, not a desire to start a family, lie at the heart of the decision by many women to leave a career in science, a U.S. study indicates. That\'s the conclusion of research by the University of Texas-Austin and Cornell University examining the factors behind the shortage of women in science, technology, engineering and math (STEM) fields, a Cornell release reported Monday. \"We don\'t find support for the idea that women are opting out of the labor force to remain home with children, as relatively few departed from the work force completely,\" Cornell researcher Sharon Sassler said. \"Of note is that family factors -- such as having one\'s first child, or having additional children -- cannot account for the differential loss of STEM workers compared to other professional workers, because exits from the STEM work force tend to occur before women have begun their marital and childbearing histories.\" While pursuing an advanced degree and viewing one\'s job as rewarding tend to increase retention in other professions, the researchers found, such investments made by women in STEM do not seem to stimulate commitment to STEM in the same way. \"Gender barriers are hindering women from entering into STEM jobs, and even among those women persistent enough to enter the STEM labor force, transitions out of STEM jobs transpire relatively early on in their careers,\" Sassler said. A substantial proportion of women who are trained in the field and begin working in STEM jobs rapidly exit such jobs, she said. \"Additional attention is needed to the field of STEM itself to better understand why so many of the highly skilled workers trained -- at great expense -- for these fields are exiting,\" she said.