The Supreme Court of Canada on Thursday refused to hear the case of a B.C. mom seeking to change Canada's employment laws so that they grant maternity leave to adoptive parents.

Under the federal Employment Insurance Act, birth parents receive a total of 50 weeks of leave when they combine parental and maternity leave.

When Patti Tomasson of Vancouver adopted children in 1999 and 2003, she applied for the benefits but received only a portion of the time — the 35 weeks of parental leave.

She fought the Canada Employment Insurance Commission, arguing that their refusal to grant her the extra 15 weeks of maternity leave given to birth parents went against the constitutional right of equality.

When she brought her case before the Federal Court of Appeal in August 2007, it ruled that Tomasson did not qualify for maternity benefits because she did not undergo the "physiological and psychological experience" of pregnancy and childbirth.

Adoption advocates have argued that the 15 weeks of maternity leave are more than enough time to recover from childbirth. They say most of that time is actually spent bonding with the child, something adoptive parents should also be able to do.