The teaching of sex and relationship education (SRE) has long been a source of controversy. The decision to make it statutory from the age of 11 - and introduce certain aspects of it in primary schools from 2011 - has led to often-sensationalist headlines in some newspapers, despite the fact the UK has one of the highest teenage pregnancy rates in Europe.

A recent study by the National Foundation for Educational Research surveyed 17 countries worldwide to look at what was offered in terms of sex education to pupils, and from what age.

In nearly every country surveyed - Italy being the notable exception - SRE is part of the statutory curriculum. The age that schools start teaching SRE varies, with some countries starting as young as four (Ireland) or six (Norway).

In most countries, at primary stage SRE tends to avoid specific reference to intercourse. As pupils get older the content becomes more sophisticated. In Norway, for example, 12 to 13-year-olds talk about diversity in sexual orientation. In the majority of countries parents do not have the right to withdraw their children from SRE, though this is permitted in Singapore and Sweden.

In England and Wales, as the national curriculum has become more circumscribed, the state has seemingly become less willing to leave traditional family responsibilities to chance, preferring to trust it to the education system. How well schools manage their roles is, of course, another matter entirely.

John Howson is director of Education Data Surveys, part of TSL Education.