Updated

MADISON, Wis. -- A woman who raised two adopted children for years in a same-sex relationship is not considered their parent under Wisconsin law, an appeals court ruled Thursday.

The court ruled against a woman who was seeking legal guardianship of two children for whom she had been a stay-at-home mother. The District 4 Court of Appeals ruled that only the woman's former partner is their parent since the adoptions were done under the partner's name.

"It's another slap in the face to gays and lesbians that we're not equal. We're not parents," said the woman's attorney, Michele Perrault.

The woman, identified in court records only as Wendy, had been in a domestic relationship for 7 years before the couple decided to adopt a child from Guatemala in 2002. They adopted a second child from there in 2004.

Same-sex couples do not have adoption rights in Wisconsin, meaning that only one of them can be considered the legal parent. In this case, Wendy's partner, identified in court records as Liz, was named the legal parent so the children could be added to her health care plan.

Wendy agreed to quit her job and stay at home to look after the kids while Liz, an attorney, was the family's breadwinner. The couple split up in 2008, and agreed to an informal co-parenting relationship to share custody.

However, Wendy wanted legal recognition of her rights to the children, and she petitioned a court to be named a legal guardian. Perrault said that would have protected her right to make medical and educational decisions in the best interest of her children, among other things.

Liz initially agreed, but then objected to the petition for guardianship. A Dane County judge sided with Liz then Wendy appealed.

The appeals court ruled that "parent" is defined under Wisconsin law as someone who is either a biological or an adoptive parent, and Wendy is neither.

The court also rejected her argument that she should be granted guardianship because the children would be harmed by "depriving them of one of the two persons who has raised them from infancy."

The court ruled she still shares custody under the informal arrangement, and only factors such as abandonment or neglect would justify guardianship to be granted to a "third party," which she hasn't proven.

Tamara Packard, a Madison lawyer who serves on the board of Fair Wisconsin, a gay rights group, said the practical impact of the decision is relatively narrow. It should not affect cases in which gay couples have consented to guardianship agreements for their children but only those in which one of the partners objects, she said.

"It gives the biological or adoptive parent an incredible amount of power and control over the nonbiological, nonadoptive parent that can be used in ways that aren't healthy," she said. "It does underscore the significant handicap that same-sex couples have in forming and safeguarding their families."