CARVER, Mass (AP) - A Carver man has pleaded guilty to driving under the influence of drugs and causing a head-on crash that seriously injured a pregnant woman, who lost the fetus as a result.

The Plymouth County District Attorney's Office said Thursday that 25-year-old Christopher Reagan also pleaded guilty to aggravated assault and battery by means of a dangerous weapon in the February 2015 crash. He will serve up to four years in prison.

Authorities say Reagan failed to hit the brakes and whipped around a curve on a street in Carver. His vehicle crossed traffic lines and collided with the victim's car.
The woman sustained a traumatic brain injury.

Officials say prosecutors couldn't charge Reagan with motor vehicle homicide because the fetus was determined not to be viable outside the womb.