Two of the women, Erin and Marianne Krupa, a couple, spent more than $25,000 on failed infertility treatment in five months
Four lesbian women are suing a U.S. state for discrimination for insisting women have unprotected sex with a man to prove they are infertile and claim insurance cover for treatment.
In a landmark case, the women filed the complaint after being rejected by their insurer for infertility treatment and arguing the law discriminated against infertile gay women by forcing them - not straight women - to pay for procedures.
Two of the women, Erin and Marianne Krupa, a couple, spent more than $25,000 on failed infertility treatment in five months after their insurance claim was rejected, the complaint said.
The civil complaint filed in a federal court in the state of New Jersey adds to an ongoing debate in the United States about the rights of the lesbian, gay, bisexual and transgender (LGBT) community.
Grace Cathryn Cretcher, an attorney for the women, said she believed this was the first case of its kind with the women trying to change the legal definition of infertility to make it easier for future lesbian couples seeking to have a baby.
According to the suit, the law in New Jersey defines infertility as when a woman cannot conceive after a year or more of unprotected intercourse.
Susan Sommer, a spokeswoman for Lambda Legal, a New York City-based LGBT rights group, said insurance standards needed to be updated for same-sex couples to receive full equality,
"This lawsuit reflects the frustration and indignities lesbian and gay people endure because state laws and insurance rules continue to presume the only parents are heterosexual parents," Sommer said in an email statement.
The four women are seeking an order declaring the New Jersey insurance law is unconstitutional and discriminatory and also an injunction ordering the state to expand insurance cover for infertility to women in same-sex relationships.
New Jersey is one of 15 U.S. states to have passed laws that require insurance companies to cover infertility diagnosis and treatment, according to the National Conference of State Legislatures, which tracks state laws.
So far California and Maryland are the only states to have updated their definitions of infertility to include gay couples.
The lawsuit, filed in a Newark court last week, names the New Jersey Department of Banking and Insurance's commissioner, Richard J. Badolato, as the defendant. It did not list a defense attorney.
A government spokesman said the department "does not comment on pending or ongoing litigation".
The Krupas and the two other women, Sol Mejias and Sarah Mills, were all clients of Horizon Blue Cross Blue Shield of New Jersey, the complaint said.
A spokesman for the company said the suit takes issue with the law and not Horizon which covers "infertility services equally, regardless of sexual orientation".
The company eventually agreed to pay for infertility treatment for Krupa, the complaint said, but it was not successful.
"Horizon is committed to equality, values our LGBTQ members, and is sensitive to their unique healthcare challenges and needs," the insurance company said in an email.