SAN DIEGO -- A man was taken into custody Tuesday after police said he used a golf club to smash a pregnant driver's window in an apparent road rage incident.

San Diego police said 27-year-old Russell Woodhouse was arrested on suspicion of assault with a deadly weapon.

"He got out of the car and hit her window, and she followed him up here where he was going," said Shamika Hopson, the pregnant woman's sister.

Hopson said her 24-year-old sister Martha is four months pregnant and is considered high-risk.

"She's still shaken up right now … she's a high-risk pregnancy, anything can happen to the baby from scaring her like that," said Hopson.

She said Martha was on her way to work and was driving behind a blue Toyota sedan on El Cajon Blvd. when she decided to switch lanes.

Hopson claimed the Toyota's driver cut her sister off, and when they stopped at 54th Street and El Cajon Blvd, Woodhouse allegedly got out of the passenger side and smashed Martha's window with a golf club.

"Glass everywhere, glass on the front seat, glass on the floor, it's everywhere," described Hopson.

She said her sister followed the car to the Campus Plaza parking lot while on the phone with police.

"I don't know what's up with him, but he needs to second think about what he did," said Hopson.

Martha Hopson went to the hospital to make sure she and her baby are OK.