More than 3 million spill-proof cups for children have been recalled because of a potential for mold growth.

Mayborn USA voluntarily recalled five types of spill-proof Tommee Tippee Sippee cups made between December 2014 and March 2016, despite the company's February announcement that it would issue new valves for sippy cups.

The recalled cups all have a removable, one-piece white valve.

Cups with a different type of valve are not affected, according to the company’s recall notice, which was announced Friday.

Mold ingestion can cause gastrointestinal symptoms and infections, especially in people with compromised immune systems.

According to The Associated Press, Mayborn has received more than 3,000 reports of mold in the recalled cups.

Related: Tommee Tippee releases fix for moldy sippy cups

There have been 68 reports of children experiencing diarrhea, vomiting or other symptoms associated with drinking from a cup with mold in the valve.

Consumers should stop using the recalled cups immediately and contact Mayborn for a free replacement.