Top ranked New Zealand were too hot for the US to handle, amassing seven tries to set up a final showdown with holders England or France, who clash in the second semi-final later on Tuesday.

The States led early in the first half following a Kris Thomas try that Alev Kelter converted, but once the Black Ferns found their rhythm, there was no stopping them.

The four-time world champions took a third-minute lead when fly-half Victoria Subritzky-Nafatali touched down.

After their opponents briefly led, a Kendra Cocksedge penalty edged New Zealand back in front before she converted Woodman's opener to secure a 15-7 interval advantage.

A second Woodman score and Cocksedge penalty opened up a 16-point gap, and then New Zealand underlined their quality during a blistering final quarter that saw them claim four tries in 15 minutes.

Woodman added two more, then replacement hooker Te Kura Ngata-Aerengamate claimed another touchdown before Kelly Brazier completed an emphatic second-half display and Cocksedge converted.