Workplace protections for transgender people are unlikely to see major changes following the Trump administration’s latest push to define “sex” under federal law, according to former agency officials and industry professionals.

A Department of Health and Human Services memo, first reported by the New York Times Oct. 21, once again brought the controversial topics of sexual orientation and gender identity into the spotlight. The definition, as proposed, would exclude transgender individuals who don’t identify with the sex they were assigned at birth.

But while the health agency might change its definition of “sex,” the state of workplace anti-discrimination protections for...