Thirteen percent of the 10274 babies born at the Coronation Hospital in Johannesburg last year had foreign mothers, the DA said yesterday.
This was placing great stress on South African healthcare facilities, DA health spokesman Jack Bloom said.
"Treatment is free for maternal health services, even for foreigners," he said.
"My estimate is that it costs the hospital more than R10million every year to help foreign mothers to give birth in South Africa."
Bloom said many of these 1309 mothers were from countries like Zimbabwe, Malawi, the Democratic Republic of Congo, Somalia, Pakistan and India.
He said a change in policy was required . "The influx from neighbouring countries is probably inevitable, but I think we need to look after our own interests first."
Vusi Sibiya, spokesman for the Gauteng Department of Health, said: "The government policy regarding maternal health services does not discriminate. The services are for free, irrespective of whether they are illegal immigrants or not." - Sapa