Mary Read, head of the School of Education at the University of Hertfordshire, said that secondary school teaching courses, which traditionally are hardest to fill, might be worst affected by the delays.
“Anecdotally, the people most likely to drop out at this point are people from STEM [science, technology, engineering and mathematics], which of course is the government’s priority,” she said.
Candidates for secondary school teaching in science and maths, “where you are always working hard to recruit good people”, were “very attractive to other employers”, Dr Read added.
“If those people feel that we aren’t able to make a commitment to them, it is possible that they will pull out.”
Dr Read said that Hertfordshire had “little alternative” but to begin the recruitment process, although currently it is not offering places, in line with guidance from the Training and Development Agency for Schools.
She said there had been “annoyance” within the academy over the lack of information about the delays: “The information we had from our regional links was that we would hear just before Christmas and, if not, immediately after. So the fact that we’ve gone on nearly a month after that is difficult.
“All we’re being told is that we can’t be told, but we don’t know why.”
A letter sent to education secretary Michael Gove from James Noble Rogers, executive director of the Universities’ Council for the Education of Teachers, warns that “many applicants are withdrawing and seeking alternative career options”.
Dr Read said: “The longer [the uncertainty] goes on, the chances increase that you will have people who can’t give notice in their current roles and others who may be unable to make the necessary childcare arrangements.”
This was likely to lead to higher dropout rates, she added.
A spokesman from the Department for Education said it was “not unusual” for numbers to be released around this time, adding that the department would be making an announcement about the allocations “shortly”.