The woman, who is eight months pregnant, was with her partner and a seven-year-old girl. They were among eight people who had to be rescued by Avon Fire and Rescue Service's hovercraft at the beach. Words: PA
A spokesman said: "A woman, thought to be eight months pregnant, her partner and a young girl aged around seven, were...assisted to safety.
"The woman was stuck up to her waist in the mud."
The five others who were rescued included a teenage boy suffering from exhaustion, who was with a man who was trapped up to his knees in mud.
Three men aged in their 20s were also rescued.
Firefighters warned that the tide in the Bristol Channel can turn very quickly and advised visitors to check tide times and not to go out too far.
The area is well known for its treacherous mud. Only last week, a teenage boy became trapped up to his shoulders in the mud at Weston-super-Mare, reports the Daily Telegraph.
And in 2002, a five-year-old girl died after getting trapped in the mud at nearby Barrow beach.
Have you got stuck in the mud on one of these beaches? Should there be more warnings on the beach? Tell us below.
Two women rescued from mud in Devon
Dramatic rescue as walker gets stuck waist-deep in mud on Dartmoor
Mother rescues baby elephant stuck in mud pool
Dramatic rescue of drowning boy in Cornwall: Video released