You know those baby dolls they give to teenage girls that cry and wet themselves in order to show them just what a bad idea it is to get pregnant at this stage in their lives? They’re not exactly working as intended, according to a new study.

These “baby simulators” are actually having the opposite effect: girls who got them were 36 percent more likely to get pregnant by age 20 compared to schools that just used standard school curriculum. It’s a finding that surprised the scientists involved in the research, who at the very worst expected it to have no effect or be a very small deterrent.

Researchers followed more than 2,800 teen girls between 13 and 15 years of age at 57 schools in Australia, and kept tracking them until they reached 20 years of age.

The reality was that instead of causing teen girls to become annoyed by the babies and not want them, they actually became attached to their fake babies. Not only were the teen girls more likely to get pregnant, but they were also more likely to keep them.