One in five students could not study a degree subject that interested them because they did not have the right subjects from school or college to progress onto the course, a report suggests.

This is most apparent for degree courses, such as medicine and dentistry, maths, economics or languages, which require a specific set of qualifications, according to the university admissions service.

A survey by Ucas suggests that two in five students at university believe more information and advice would have led to them making better choices.

Meanwhile, nearly one in three students said they did not receive any information and advice about apprenticeships from their school.

Ucas chief executive Clare Marchant is calling for careers information and advice to be embedded in primary schools and the start of secondary school “to raise aspirations from an early age”.

But the school leaders’ union has blamed the Government for providing “piecemeal and inadequate” support for careers education, adding that universities “have not helped” by making unconditional offers.

The Ucas report, which highlights the impact of qualification and subject choice on students’ futures, found that one in three first realised in primary school that higher education was an option for them.

The analysis, based on a survey of more than 27,000 students at UK universities and colleges, suggests that advantaged students are 1.4 times more likely to do this than their disadvantaged peers.

Just over a quarter (27%) of disadvantaged students said they started thinking about higher education at primary school, compared to nearly two in five (39%) of their more advantaged peers.

Nearly three in five (58%) pre-clinical medicine students said they had thought about their preferred degree subject before starting GCSEs or National 5s, compared to only 18% of business studies students.

One in four students say their parents or carers were their biggest help in determining their choice of degree course, and many follow similar pathways.

Students with a parent or carer who is a medical practitioner are eight times more likely to study medicine or dentistry, according to the analysis from Ucas.

Disadvantaged students are more likely to report not having the relevant subjects to study medicine, it adds.

More than a quarter of students said they would make different GCSE or National 5 choices now they know what their degree course entails – and  32% would choose a different post-16 option.

Ms Marchant said: “Whilst choice is a core part of the UK higher education system, it is essential that students know how to navigate this. No student should unknowingly close the door to their career aspirations.

“We know that early engagement raises aspiration. The data showing that disadvantaged students tend to consider the prospect of higher education later than their more advantaged peers clearly demonstrates the need to embed careers information, advice and guidance within primary schools and early secondary years to raise aspirations from an early age.”

In a foreword to the report, Salsabil Elmegri, vice president Further Education at the National Union of Students (NUS), said: “Improvements must be made to enhance early engagement, in order to give students the opportunity to fully consider the best path for them, whether that is a vocational course, an apprenticeship, or an academic degree.

“Students deserve to know what they’re signing up for, and any decisions concerning their futures should not be rushed into or driven by pressure.”

Geoff Barton, general secretary of the Association of School and College Leaders (ASCL), said: “It would be great to provide more careers advice and information but schools and colleges do need to be sufficiently supported and funded to deliver that aspiration.”

He added: “Unfortunately, the Government dismantled national careers advice services in 2012 and left schools and colleges to pick up the pieces while squeezing their budgets.

“Matters have improved since then through various initiatives but Government support is characteristically piecemeal and inadequate.

“And many universities have not helped by the use of inappropriate unconditional offers which incentivise students to take courses that may not be the best choice for them.”

A Department for Education spokeswoman said: “We have invested over £100 million this financial year alone towards high-quality careers provision, including the rollout of the Enterprise Adviser network reaching more than 4,000 schools and colleges and connecting 3.3 million young people to future employers, and National Careers Service support to those who need it.

“We know there is more to do, and pledged earlier this year as part of our Skills for Jobs White Paper to expand this offer, rolling out services to all secondary schools and colleges in England.”