The reason why the over-25s find it more difficult to gain employment could be partly because they are more expensive to recruit, but also because family commitments mean they are often less flexible about where they can go.
Evidence collected by the Higher Education Statistics Agency shows that mature students made up just under half of the 199495 PGCE cohort whose destinations are known.
But analysis of the statistics shows that 10 per cent were still looking for employment or training after completing their courses compared to 6 per cent of the under-25s.
John Howson, a senior lecturer at Oxford Brookes University and a specialist in teacher recruitment, said: "One of the problems with the market-oriented system where people can train where they want and teach where they want is that it is inefficient.
"It means that there is going to be wastage and there is no mechanism in place to cope with that."
According to HESA, 16,793 students gained PGCEs in 1995. The agency was able to ascertain the first destinations of 14,308 students - or 85 per cent of them - but it is not known what happened to the missing 2,485 newly qualified teachers.
Of the 14,308 students, 12,370, or 86 per cent, gained work - the bulk of them (12,087) in education in jobs ranging from nursery school teachers to university lecturers.
The biggest employment areas outside teaching were literary, artistic and sporting jobs which attracted 42 students.
Thirty-seven students said they were working as sales assistants and check-out operators while 32 had become social welfare associate professionals.
Other jobs that PGCE students found themselves in included management and clerical positions, childcare posts, catering, computer programming, town planning and assembly-line working.
Mr Howson said that an 80-plus percentage take-up of people going into work after the course would be "pretty good".
Figures released by the Department for Education and Employment earlier in the year showed that some 73 per cent of PGCE students in 199394 were teaching in schools.
Eighty per cent of under-25s who gained PGCEs in 1992 were working as teachers by March 1993 but only 61 per cent of 44- to 54-year-olds and two-thirds of the 35-44 year age group had found jobs.
Mr Howson said: "There is an in-built problem in our system of teacher training which has no means of regulation.
"Mature students can only work in certain areas and they are not necessarily able to find those jobs while the under-25s can."