Consumers who try to sign up for insurance after the Obamacare open enrollment period will soon need to submit proof that they are eligible for most special enrollment periods, federal health officials announced Wednesday.

This new confirmation process, which is expected to start in the next few months, will only affect those living in the 38 states that use the federal Healthcare.gov site.

It addresses complaints from insurance companies that the Centers for Medicare and Medicaid Services was allowing too many people to buy insurance after the open enrollment deadline passed. This, insurers said, left them with many consumers who waited until they were sick to sign up and then dropped coverage after they received treatment. And the companies claim that created a sicker-than-expected pool of customers that was contributing to the losses on Affordable Care Act exchange plans.