Nicola Brewer said the extension of paid leave from six to nine months for new mothers and the absence of equal rights for fathers meant some employers were wary of recruiting women of child bearing age.
She questioned whether the policy inadvertently entrenched the stereotype that women are the primary carers and should therefore "pay the career penalty" for having a child.
Anne Fairweather, head of public policy at the Recruitment and Employment Confederation, said employers who fail to consider female candidates of childbearing age are missing out on a large pool of talent.
She said more advice and support was needed to help employers see pregnancy in a positive light and deal with it in a way that benefits both parties.
"A good recruiter will work with an employer to find ways of managing pregnancy in the workplace," she remarked. "Whilst it can be a challenge, especially for smaller businesses, use of flexible work options, such as temporary staffing can help resolve issues."
