The majority of company bosses make an assessment on whether an employee is likely to get pregnant before deciding whether to offer them a job, according to a survey by Employment Law Advisory Services (ELAS).

Over half (52%) said they took factors such as age and whether a candidate had just got married into account when recruiting and 76% of managers said they would not hire someone if they knew they would get pregnant within six months of starting the new job.

Employers are not allowed to ask candidates if they intend to fall pregnant but 86% said they would feel cheated if a new recruit announced they were expecting a baby just weeks after joining.

But ELAS warned employers they were on very dangerous ground if they discriminated against potential recruits on the chance that they may fall pregnant.

"It is a very dangerous area and you simply cannot ask the question about plans for a family in an interview," said Peter Mooney, head of consultancy at ELAS. "For many bosses it is down to the bottom line: a pregnant member of staff will cost money. However a visit to a tribunal can be even more costly."