A Florida court has granted equal parental rights to two lesbian women who created a child using the eggs from one of the women, while the other carried the baby to term. It ruled that egg donors may acquire parental rights to children resulting from their gametes under the Florida and US Constitution.

The couple, who have now separated, were involved in custody proceedings over the child, born in 2004, after the woman who provided the eggs sought legal parental status. The birth mother – who under Florida law was automatically considered to be the child's legal mother – reportedly left for Australia with the child, before returning to the USA. The sperm was provided by an anonymous donor who waived all his rights over the child.

A circuit judge initially made a ruling in favour of the birth mother, but the decision was later overturned by the Florida Fifth District Court of Appeal in December last year. The court said that Florida law, which grants parental status to the woman who carries the child only, is out of date and violates the US Constitution.

According to the Orlando Sentinel newspaper, the court said: 'This is a unique case, and the appellate courts in Florida have never before considered a case quite like it'.

Under UK law, the birth mother – who carries the child - is considered to be the child's legal mother even if she has no genetic connection to the child. The law was recently updated to recognise same-sex couples as legal parents of children. The partner of a lesbian birth mother in a civil partnership can now be considered in law to be the child's second parent, if the child was born after 6 April 2009, and can be named on the child's birth certificate. The situation is, however, more complex where the couple is not in a civil partnership.

Speaking about the Florida case to the Sentinel, Professor Nancy Polikoff, who specialises in family law at the American University Washington College of Law, said: 'Any ruling that supports the right of a same-sex couple... is important for its willingness to recognise that these families exist and a child raised in this environment shouldn't be forced to give up a parent'.

The case has reportedly been passed back to the trial judge to determine details of custody, visitation and child-support.