Van Niekerk was born in Pretoria and grew up on the family farm located in the Orange Free State. He studied medicine and surgery at the University of Pretoria, and graduated in 1959. He worked as a researcher for the Roswell Park Memorial Cancer Institute in Buffalo, New York, United States, before returning to South Africa in 1960 where he worked at the Department of Obstetrics and Gynecology at the University of Pretoria.
