WHILE big bellies aren't selling in Singapore, the opposite is happening in the US.

Pregnant and nursing models are so prized that a specialised New York-based modelling agency, Expecting Models, was formed to capitalise on the blooming niche market.

Set up in 2001 by former model Liza Elliott-Ramirez, it claims to be the only professional agency dedicated exclusively to representing pregnant models.

It has reportedly seen a 45 per cent increase in business since its inception, and has bureaus in California and Florida.

According to Elliott-Ramirez, the demand for pregnant models became obvious to her when she was late in her own pregnancy and wanted to continue modelling.

Interestingly, she claimed she managed to book more gigs during her pregnancy than any other period in her 20-year career.

Now, she counts Liz Lange, The Gap, Old Navy, Target, Bloomingdales, American Express, Verizon and The Olive Garden as her biggest clients.

Her roster of 150 models have graced hundreds of magazine covers and high-end shoots could earn pregnant models up to US$40,000 ($60,400) a day.

Elliott-Ramirez, 33, told The Insider Online: 'They are actually making more than the mainstream models because there is such a level of risk involved with being pregnant on a set.'

Expecting Models has become such a phenomenon that it even has its own documentary TV series, Runway Moms, now showing here on Discovery Travel & Living (StarHub Ch 16) on Saturdays at 5pm.