Pregnant woman assaulted during handbag snatch

A heavily pregnant woman has suffered cuts and abrasions after a man dragged her down a concrete walkway while snatching her handbag in Sydney's west.

The 23-year-old woman, who is nine months pregnant, was walking from Canley Vale Station to meet her husband last night when her bag was snatched.

The alleged thief ran off but a passer-by chased the offender before losing him when he started to cut through backyards.

The offender has been described as being aged in his 20s with a medium build and short brown hair, wearing a grey tracksuit top with blue stripes.