SAN FRANCISCO — The petite woman in a pinstriped suit recalled her last visit with her 8-year-old twin daughters. It had been months since she had seen the girls, and a court had just ruled that she had no legal right ever to be with them again.
"I told my girls they needed to know that every moment of the day, every minute of every hour, they are in my mind and they are in my heart," said the 42-year-old Marin County resident, her face wet with tears.
Known in court papers only as K.M., the woman is the girls' genetic mother. She could not bear a child because of a diseased uterus; her partner, a woman known in court as E.G., was infertile. K.M. donated her eggs to her partner. Using a sperm donor, her partner conceived, and the women raised the twins together for five years.
Three years ago, the couple split up. K.M. says her former partner no longer allows her to visit or talk to the girls. Courts have ruled that K.M. has the legal status of an egg donor and no parental rights, in part because she signed a standard donor form at the fertility clinic.
The case, which K.M. has appealed to the California Supreme Court, is one of a growing number around the country in which new reproductive technologies and nontraditional families collide with old legal principles.
Though courts often stretch to give children both a legal father and a legal mother, the formulas for deciding parenthood frequently do not fit the realities of same-sex couples.
"When you read the legal cases," said Deborah Wald, a family-law attorney in San Francisco, "what becomes crystal clear is that children of same-sex couples aren't entitled to the same level of protection as children of opposite-sex couples."
Opponents of same-sex marriage find that entirely appropriate. Court battles between gay parents show why couples of the same gender should not have children, they say.
"Every child needs a mom and a dad," said Dale Schowengerdt, a staff lawyer for the Alliance Defense Fund, which wages legal battles promoting traditional religious views. "Every male couple deprives a child of a mom; every female couple deprives a child of a dad."
But advocates for gay couples say changes in technology and family structures make those arguments out of date. The last census found about 27,000 households in the state where children were being reared by parents of the same gender.
Technology now allows two women to become the natural mothers of a child, two men to mix their sperm and create a baby with a donated egg and a hired surrogate.
"Neither the Legislature nor the courts are keeping up at all with the changes," Wald said.
In ruling against K.M., a Court of Appeal in San Francisco conceded that the decision would have "harsh consequences" for the children.
"There is no dispute that K.M. acted as an affectionate mother to the girls, and that the girls are emotionally attached to her," the judges said, while maintaining that the law left them no choice.
Expanding the legal definition of a parent could allow others -- child care providers and relatives or friends of a child, for example -- to seek parental status, courts have said.
"Functioning as a parent does not bestow legal status as a parent," the appeals court ruled in K.M.'s case.
The law in California is changing. Under a new statute that will take effect next year, same-sex couples who are registered with the state as domestic partners will both be legal parents to children born into their households. But the law will not affect children born before Jan. 1, 2005.
Same-sex couples who already have children can ensure parental rights using other legal processes, including adoption. But until recently, some counties in California refused to let same-sex couples employ adoption procedures, Wald said. Moreover, she said, many couples never go through the formalities.
"I actually think it is not all that uncommon for people to never get around to getting their legal paperwork together in many areas of their life," she said.
Courts in several other states have granted custody or visitation rights to nonbiological parents who had not adopted. And just weeks ago, in the first decision of its kind in California, a Court of Appeal in Los Angeles ruled that a woman might be entitled to some parental rights over her former lesbian partner's objections if she could show that she had treated the partner's child as her own.
Despite that ruling, most lawyers say adoptions remain the safest route for same-sex couples. "If you don't do a second-parent adoption in California, the other mom can be completely cut off from her child and the child cut off from somebody she completely considers her parent," said Nancy Polikoff, a professor at the American University Law School in Washington, D.C.