AMQ Health General Practice, Macquarie University, Sydney, NSW2109, Australia.

BFaculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW2109, Australia.

CSydney Sexual Health Centre, Level 3, Sydney Eye Hospital, 8 Macquarie Street, Sydney, NSW2000, Australia.

DFamily Planning Australia, 10 Avenue of the Americas Newington, Sydney, NSW2127, Australia.

EShanghai Pudong New Area Gongli Hospital, No 219 Miaopu Road, Pudong New Area, Shanghai, China.

FGeneral Practice Clinical School, Sydney Medical School, Faculty of Medicine and Health, University of Sydney, Sydney, NSW2006, Australia.