A girl's first sexual intercourse is often unplanned and may put her at risk of STDs and HIV infection as well as unwanted pregnancy. The high prevalence of HIV among 15–24 year olds in KwaZulu Natal suggests that sex is initiated at an early age. This paper is based on a 1999 survey in SouthAfrica which identified age of sexual debut and childbearing among adolescent girls in KwaZulu Natal. Of a sample of 796 girls, almost half had already had first sexual intercourse at a mean age of 16. Of these, 44 per cent reported having communicated with their first partner about preventing pregnancy, of whom 36 per cent were able to use a contraceptive method. The majority used a male condom, the pill or injectable. Similarly, 30 per cent had used a method, almost all of them a male condom, to prevent a sexually transmitted disease at first sex. About half of the girls had ever been pregnant and a large percentage of these indicated that the pregnancy had been unwanted. If sexuality education were to begin before puberty, at age 9–10 and in primary school then many more girls would be in a better position to make informed choices about their sexual activities by the time they begin to engage in sex or reach menarche.