A scheme by investment bank Goldman Sachs to pay for new mothers to courier their breast milk home from work trips drew praise and criticism on Tuesday, with some campaigners concerned the move could pressure women to cut short their maternity leave.

Goldman Sachs said it hopes the initiative - which will see the global firm pick up the bill for breastfeeding employees to chill and ship their milk when travelling for work - will make "the balancing act a little easier" for mothers in its ranks.

Yet the scheme - the latest from blue-chip companies seeking to retain female talent amid growing pressure over the lack of women in leadership roles - must not penalise women who choose to take longer maternity leave, said healthcare charity BPAS.

"In a culture where time is money, we must be careful that the legitimacy of such a choice is respected, and not undermined by ever more elaborate offers of support which are designed to get women back to their desks," a spokesman for the British Pregnancy Advisory Service told the Thomson Reuters Foundation.

With outrage over gender inequality in the workplace - which is estimated by the World Bank to cost the world $160 trillion - rising in recent years, leading businesses are taking action.

Tech giants Apple and Facebook have started paying for female staff to freeze their eggs - in order to delay motherhood - while firms such as Deloitte and Microsoft have return to work programmes for women who pause their careers to raise children.

Katushka Giltsoff, a British recruiter for executive roles, praised the Goldman Sachs scheme as "creative and innovative".

"I think actually it takes pressure away," she said. "A lot of mothers want to return to work and be able to mix and match."

Edit Schlaffer, executive director of the Women Without Borders charity, said it was a positive "small step" for working mothers, but that they should demand even more support at work.

"This balancing act women are faced with every day is a big problem," she said.

The World Health Organization (WHO) recommends that babies be breastfed exclusively for their first six months then have a diet of breast milk and other food until they are two years old.

In practice, many mothers give up breastfeeding earlier, with studies in countries from Australia to the United States suggesting that a demanding job can be a significant barrier.