Writing on Instagram, Ms Phelps highlighted how unusual it was to see a pregnant woman walk in a fashion show.
"I've been going to fashion shows for 21 years and I've seen a pregnant model on the runway exactly one other time. Something to think about," she wrote.
The post has already been 'liked' over 17,600 times.
The artist, due to give birth next month, also posted a picture of her moment on the ramp on Instagram.
"I am 38 weeks pregnant and it's wonderful to see myself represented on the runway," commented one person on the post. "Among the many, many hard things about pregnancy is feeling ignored and marginalized by fashion and retail at a time when you have so many conflicting feelings about how your body is changing."
But not everyone agreed.
"Shouldn't we be glad the pregnant models are taking some time off to care for themselves and the soon to be born little human they have to carry around 24/7, instead of working their a** off on a catwalk in uncomfortable clothes. Not saying they can't do it, hell that woman looks gorgeous but I don't think I would be stressing around on fashion shows if I was over 6 months pregnant," commented one person.
"Totally agree! I wouldn't want to model while pregnant. But, boy it'd be nice if designers designed maternity wear," commented another.
And while the sight of a pregnant woman on the runway certainly is rare, India has seen more than one mum-to-be walk down the catwalk. Last year, supermodel Carol Gracias showed off her baby bump while walking for Gaurang Shah at the summer-resort edition of Lakme Fashion Week.
Actor Kareena Kapoor Khan also walked the ramp for designer Sabyasachi Mukherjee while pregnant.
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