The woman, seven months pregnant, was taken to hospital as a precaution along with two men, the drivers of the other vehicles.
The crash came about 9.30pm when Na Pimpa, 61, turned right from Thepkasattri Road into the bypass road and encountered work being done at the road neat the intersection.
His car veered across the median strip into oncoming traffic, collecting cars being driven by Pongnarin Chooman, 25, and the pregnant woman.
All three were taken to hospital but did not appear seriously injured, according to Kusuldharm Phuket Foundation paramedics who attended the triple crash.
About 30 minutes later, a man in a car crashed into one of the new lightpoles in Thepkasattri Road, bending the pole and breaking the car into small pieces.
The driver was taken to Thalang Hospital.