The findings of research published recently by the Employment Law Advisory Services (ELAS) have been described by one politician as "worrying", News Wales reports.
According to the study, over three-quarters of managers questioned reported they would not take on a woman recruit if they were aware she intended to become pregnant within six months of starting a job.
In addition, some of those questioned were found to ask candidates during interviews if they plan to have children, a practice which is banned under sex discrimination law.
Commenting on the issue, Lesley Griffiths - a member of the Welsh Assembly - stated: "This research provides some very worrying findings and trends for women seeking employment or already in employment within an organisation."
She added that bosses who engage in the practice of weighing up pregnancy risk among potential workers "need to be made aware they are breaking the law".
Julie Morris, a partner in the employment department at Russell Jones & Walker said: "These statistics are shocking and show just how prevalent this type of sex discrimination still is, and how acceptable it is deemed by many employers to be.
"Claims by those discriminated against upon recruitment have been rare, owing to the fact that there is often a lack of evidence available. However, these statistics show the need for individuals to come forward and to speak out where they think that they have been refused employment because of their future family plans."
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