Antenatal visits, scans and postnatal visit are claimed through Medicare. You can check the rebate amounts here:
http://www9.health.gov.au/mbs/search.cfm?q=&sopt=S

The Item numbers are:
16401 Obstetric Initial Visit
16500 Antenatal Visits
16404 Postnatal Visit
16590 Pregnancy Management Fee
55702 onwards - Scans