Despite anti-discrimination laws, some employers are still finding ways to cut ties with their pregnant employees, new research finds.

A study in the journal Gender and Society discovered that to get around the Pregnancy Discrimination Act of 1978 — a law that prohibits employers from firing a woman just because she is pregnant — employers vilify pregnant women as poor performers and tardy employees.

Although such concerns may, at face value, seem legitimate in a business sense, researchers say the same policies and rationale are often not applied to nonpregnant employees, including those with worse records of performance and attendance.

"This strategy of portraying pregnant workers as undependable and costly seems to legitimize their terminations to external audiences," said Reginald Byron, one of the study's authors and an assistant professor of sociology at Southwestern University in Texas.

Byron — along with co-author Vincent Roscigno, a professor of sociology at The Ohio State University — analyzed 70 verified cases of pregnancy-based firing discrimination that were handled by the Ohio Civil Rights Commission between 1986 and 2003, plus an additional 15 cases that were processed between 2007 and 2011. Among their findings were that pregnancy accounted for 40 percent of all gender-related firing cases and that poor performance was the reason employers cited most frequently for terminating pregnant workers.

Additionally, 15 percent of employers claimed pregnant women were fired because of poor attendance and/or tardiness, while 10 percent of employers cited "business needs, profit and efficiency" in pregnancy discrimination cases.

One example the researchers cite in the study is the case of a woman who was fired from her job as an assistant restaurant manager after she became pregnant. Her supervisor claimed that the company was restructuring and needed to reduce its number of assistant managers from three to two. But after she was fired for "business reasons," the restaurant hired a man to fill the exact same position that was supposedly no longer needed.

"Some employers think pregnant women will be distracted both in the present and in the future," Byron said, adding that many pregnancy-related firings stem from stereotypes of what "ideal" workers should look like.

Byron said part of the problem is that existing laws are full of gender-laden economic loopholes, such as the Family and Medical Leave Act of 1993, which provides a maximum of 12 weeks of unpaid job-protected leave during any 12-month period but does not apply to private-sector employers with fewer than 50 employees and does not grant leave to employees with less than one year of tenure.

Some states have their own laws that are broader than the federal law, but even with those in place, researchers said some companies are reluctant to change the way they are run.

"Organizational culture can be very difficult to change," Byron said. Pregnancy discrimination only compounds other gender-based employment inequalities women face in the workplace in such areas as hiring, wages and harassment, he added.

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