The pregnant woman and her husband were said to be heading towards Putatan from the Inanam direction when the 7.10pm incident occurred.
She was subsequently sent to the hospital by paramedics who arrived later.
It was learnt that the incident occurred when a Vigo vehicle crashed into a lamppost after its driver attempted to avoid hitting an Alphard vehicle driven by a 30-year-old man who suddenly made a U-turn at the junction.
The impact caused the lamppost to collapse on the opposite road on which a Fortuna vehicle driven by a 40-year-old man and his wife was passing through.
The Fortuna driver, however, managed to step on the emergency brake to avoid crashing into the lamppost but this, in turn, resulted in their vehicle being rear-ended by the Myvi vehicle driven by a 30-year-old man and his five-month pregnant wife.
The Myvi vehicle was then rear-ended by a Perdana vehicle driven by a 32-year-old man.
All four vehicles were badly damaged in the accident, while the Alphard vehicle and Vigo vehicle were only slightly damaged.