The Affordable Care Act is being challenged in federal court again and this time there could be huge repercussions for people seeking cancer screenings, contraception, or breastfeeding support.

According to Axios, a pending federal case will determine if the section of the legislation that requires preventive services coverage is unconstitutional.

If the plaintiffs of Kelley v. Becerra are successful in their challenge, millions of Americans could lose access to free preventive services such as tobacco-cessation services, vaccinations, and physical and developmental screenings for children.

Attorneys for the plaintiffs and the federal government will argue their case before Judge Reed O'Connor Tuesday at a federal district court hearing in Fort Worth, Texas.

Ruling that the law is unconstitutional and should be overturned, O'Connor is the same Texas judge who ruled in favor of the plaintiffs in the last major Affordable Care Act case, according to Axios.

That case eventually went to the Supreme Court, where the plaintiffs lost in a 7-2 decision last summer.

The Obama-era law mandates that most private healthcare insurers, not just those participating in the government marketplaces, cover four categories of preventive services without cost sharing, which is meant to increase enrollee participation.

Recommendations and guidelines from the U.S. Preventive Services Task Force, the Advisory Committee on Immunization Practices and the Health Resources and Services Administration must be covered, as per the law.

According to The Commonwealth Fund, the recommendations total more than 100 services.

If the plaintiffs come out on top in the new challenge, the Affordable Care Act's preventive services mandate would become optional, according to Axios, and healthcare insurers could drop coverage of these services entirely or begin charging for them.

If O'Connor comes down on the plaintiff's side after Tuesday's hearing, an important question will be whether the decision takes effect immediately or is paused during the appeals process.

Andrew Pincus, a visiting lecturer at Yale Law School, told reporters yesterday that there could be "draconian effects," if the decision is made effective immediately and is not paused by either the 5th U.S. Circuit Court of Appeals or the Supreme Court.

Like the last Affordable Care Act lawsuit that O'Connor decided, Kelley v. Becerrra could ultimately make its way to the Supreme Court.

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