A pregnant 16-year-old was slashed in the back of the head after her boyfriend got into a dispute with a group of men at yesterday’s Dominican Day Parade, police said.

The girl, who told cops she was a few weeks’ pregnant, was in stable condition at Bellevue Hospital last night.

Cops said she was on 47th Street, off the parade route along Sixth Avenue, at 4 p.m. when a fight broke out.

Charged with assault were Rikeim Familia, 16, Manuel Mercedes, 20, and Annerory Dilone, 20.

At least six people were arrested for disorderly conduct in unrelated incidents.