Infant R's birth certificate lists his father's name. But the space for his mother's name is blank, and will remain so until the Indiana Court of Appeals decides who his legal mother is.

The 11-month-old boy referred to as Infant R in court documents was conceived by in vitro fertilization. His genetic parents are a northern Indiana married couple who donated the sperm and egg. His birth mother is the wife's sister, who volunteered to carry the baby.

The couple — known as T.G. and V.G. in court records — then petitioned Porter County Circuit Court to have the genetic mother's name on the child's birth certificate. The surrogate, V.G.'s sister, filed an affidavit in support of their petition.

But the judge refused, ruling that "Indiana law does not permit a non-birth mother to establish maternity. Indiana law holds the birth mother is the legal maternal mother."

On Thursday, attorney Steven Litz asked the Court of Appeals to intervene, challenging the constitutionality of Indiana's paternity law because it allows men — but not women — to establish legal parenthood.

Arizona and Maryland courts have struck down similar paternity laws in surrogacy situations, Litz said. Deputy Attorney General Frances Barrow said courts in Massachusetts and New York had ruled their paternity statutes were inadequate to deal with reproductive technology and said judges should be guided by the principle of equity.

The three-judge panel clearly sympathized with the couple, who sat quietly behind Litz throughout the hearing and declined to talk with reporters. But the judges preferred not to delve into constitutional issues. They spent much of the 40-minute hearing trying to craft a simpler solution that could be used as a precedent.

"It seems to me that everyone's singing the same song," said Chief Judge John G. Baker. "We just want to make sure we're in tune."

Litz said he didn't care how it was done, as long as V.G. was recognized as the child's mother. Barrow agreed the Constitution needn't come into play.

The problem, said Litz, is that the law hasn't kept up with reproductive technology. Indiana's paternity law was passed more than 50 years ago, when surrogate parenting didn't exist. Even Indiana's 1988 surrogacy law has been outpaced by changes in the practice, he said.

Litz estimated that as many as 5,000 to 10,000 children have been born to surrogates in the United States.

He said Indiana — like most of the 30 states with laws governing surrogacy — passed its statute in the wake of the Baby M case, in which courts initially forced artificially inseminated surrogate Mary Beth Whitehead to give up her parental rights. The New Jersey Supreme Court later overturned that decision.

But in the Baby M case the surrogate was also the child's genetic mother. Litz said most surrogacies now are in vitro pregnancies, in which the birth mother isn't the baby's genetic mother.

There are no federal guidelines for surrogacy, and state laws are "really all over the place," Litz said.

In Indiana, surrogacy isn't illegal but the contracts are unenforceable and surrogates cannot be required to give up a child, he said. The state's surrogacy law doesn't address cases in which the surrogate isn't the genetic mother.

The judges gave no indication when they might issue a ruling. If they rule in the parents' favor, the court would order the Porter County judge to recognize V.G. as the child's legal mother, Litz said.

Barrow and Litz both said it might eventually be up to the Indiana General Assembly to untangle the legal issues.