Repeal of the Obama-era Affordable Care Act could affect a little under 1.2 million Colorado women and girls with preexisting conditions, an analysis from the Center for American Progress found.

The law prohibited discriminatory coverage and pricing, and CAP’s estimate relies on a report from the U.S. Department of Health and Human Services, which noted that between 23% and 51% of the population have at least one pre-existing condition that, without the Affordable Care Act, might lead to denials of coverage, higher premium rates, or extended waiting periods for coverage.

“The ACA leveled the playing field for women by instituting rules that ensured fair access to health care coverage and services,” said Olga Robak of Protect Our Care in a statement.

“If the Trump administration succeeds in repealing the ACA through its lawsuit, women could again be charged more or denied coverage based on their medical history. These negative outcomes will affect all women but will disproportionately impact women of color and those with low incomes.”

The finding comes as the Fifth Circuit Court of Appeals prepares to rule on a case challenging the constitutionality of the law, arguing that the law’s mandate to purchase health insurance without the accompanying tax penalty undermines the Supreme Court’s 2012 finding of legality.

Were the appeals court to strike down the law, it would remain in tact nationally absent a Supreme Court ruling.

Open enrollment is ongoing from Nov. 1 until Dec. 15.