Hand we use decided in the womb

The hand you prefer to use is decided by the time you are a 10-week-old foetus in the womb, a study shows.

Scientists reached this conclusion after studying ultrasound scans of 1,000 babies - and following them after birth.

The finding could wave goodbye to a long-held view that left- or right-handedness does not develop until a child is three or four years old, says New Scientist.

Professor Peter Hepper, who led the research, found nine in 10 foetuses at 15 weeks' gestation preferred to suck their right thumbs.

His team followed 75 of those foetuses after birth and found that at 10 to 12 years old, all 60 of the right thumbsuckers were right-handed - while 10 of the 15 left thumbsuckers were left-handed.

Nervous connections to the body from the brain are not believed to start developing until 20 weeks' gestation.

Professor Hepper believes the foetus could have a preference for one side of its body simply because that side develops slightly more quickly.