The National Women’s Law Center filed a first-of-its kind lawsuit against an insurance firm, alleging Aetna discriminates against LGBTQ policyholders in its coverage of fertility treatments.

The class action, filed on Monday in federal court in the Southern District of New York, claims that Aetna’s policy provides coverage to individuals with “infertility,” defined as those who, after 12 months, haven’t gotten pregnant after having unprotected sex or after receiving “therapeutic donor insemination.” LGBTQ individuals, however, cannot conceive through sexual intercourse, relying instead on fertility treatments such as intrauterine insemination (IUI) or in vitro fertilization (IVF).