Republican Kansas Sen. Roger Marshall on Wednesday introduced a bill that would codify the legal definitions of male and female as a biological concept, rather than something based on "radical, left-wing ideology." 

The legislation comes after President Donald Trump declared that the United States would only recognize two genders. The Department of Health and Human Services released an updated guidance that only recognizes two sexes, male and female, and defines sex as a person's "immutable biological classification."

Marshall said the "Defining Male and Female Act of 2025" would codify Trump's executive order that defines sex as something that is determined at conception. 

“The Democrats’ radical transgender agenda is dangerous and wrong. We shouldn’t need legislation to tell us the basic reality that there are only two sexes, but here we are,” Marshall said. “I’m thankful President Trump has made this a top priority and signed an Executive Order on his first day in office recognizing that there are only two sexes. Congress must ensure this historic action is written into law by passing the Defining Male and Female Act.”

The legislation defines gender as based on whether a person is born with a sexual reproduction system that is designed to either produce eggs or sperm. Males produce sperm, and females produce eggs. 

The Senate bill is cosponsored by Republican Sens. Bill Cassidy of Louisiana, Tim Sheehy of Montana, Cindy Hyde-Smith of Mississippi and Pete Ricketts of Nebraska.

Illinois GOP Rep. Mary Miller introduced the House companion bill. 

“Now more than ever, we must unite to uphold the truth and biological reality established by God that there are only two sexes,” Miller said “I am proud to stand alongside Senator Marshall in introducing the House companion to the Defining Male and Female Act to ensure our nation upholds common sense and puts an end to the Left’s dangerous and extreme sexual fantasies.”

Misty Severi is a news reporter for Just The News. You can follow her on X for more coverage.