As long as you have savings, all the consultations, check-ups, scans, blood tests will all come off your savings, it's only the delivery that will come off the hospital part of your medical aid.
Most people run out of savings very quickly when pregnant cause the tests etc are expensive unless you have accumulated savings over years it helps, each visit your gynae will charge a consultation fee (inclusive of the scan), by about 12-13 weeks she will send you for blood tests (adnomality ones it's about R1800 - R2000) depending on the lab, so big chunks start coming off your savings, then they may ask you to see Dr Bhorat the fetal specialist at 13 weeks (abnormality screening) and 20 weeks (checks babies development, etc), his scans are expensive R2600 per fetus per scan, and he is the only person in his field in KZN as far as I know. at least go for one of his scans, cause he does great job and he rules out your health problems, placental problems, baby development problems, and can identify deformaties etc at 20 weeks or make you aware of future deformaties, he gives you a DVD so nice memorabilia to have. GTT (sugar testing after 24 weeks (only if your sugar is high) R300 but remember all this from you savings.
If you pregnancy is normal and healthy those are generally the minimal testing, but if things do go all that normal it will het more expensive.