In the federal system, states, as sovereigns, are immune from suits for damages, unless they elect to waive that defense. As an exception, Congress may abrogate the states' immunity pursuant to its powers under then 14th Amendment.
Congress attempted to extend the FMLA to state as well as federal employers. States rejected this extension, and claimed that any extension would be a violation of state sovereignty under the 14th Amendment.
Whether Congress has the power to apply the federal Family and Medical Leave Act to state employers.
In holding that Congress could not extend the FMLA to state employers, the Supreme Court held that the FMLA was not intended to prevent gender discrimination. Thus, state employees could take leave for gender-related concerns under state laws. Congress was more concerned with employee illness as opposed to gender, so the employee-health provision of the FMLA does not apply to gender-related issues.