Massachusetts ? A pact made by a group of teens to get pregnant and raise their babies together is at least partly behind a sudden spike in pregnancies at Gloucester High School, school officials said.

Principal Joseph Sullivan told Time magazine in a story published Wednesday that the girls confessed to making the pact after the school began investigating a rise in pregnancies that has left 17 girls at the school carrying a child. Normally, there are about four pregnancies a year at the school.

Sullivan told Time that students were coming to the school clinic multiple times to get pregnancy tests, and “seemed more upset when they weren’t pregnant than when they were.”

Some of the girls reacted to the news they were pregnant with high fives and plans for baby showers, Sullivan said. One of the fathers “is a 24-year-old homeless guy,” Sullivan told the magazine.

Superintendent Christopher Farmer said the girls who made the pact are generally “girls who lack self-esteem and have a lack of love in their life.”