Man charged over pregnant woman's death

A man has been charged with causing a pregnant woman's death through dangerous driving, after she fell from a moving car in Melbourne's northwestern suburbs.

The 32-year-old woman died in hospital after delivering a baby, who remains in a critical condition, via c-section on Saturday.

It's alleged a man was threatening to assault the woman at a home in Kiwi Retreat just before 1pm.

The incident is alleged to have continued in a car before the woman fell out onto the road while the car was still driving.

Police late on Sunday afternoon charged a 35-year-old Keilor Downs man with dangerous driving causing death.

He will appear in the Melbourne Magistrate's Court on Sunday night.